Conducting polymer based flexible super capacitors [autosaved]Jishana Basheer
Conducting polymers have potential in flexible supercapacitors due to their redox properties. Polyaniline, polypyrrole and polythiophene are promising conducting polymers. Graphene composites with these polymers improve performance by preventing aggregation and enabling fast ion transport. Future work aims to develop ternary composites and asymmetric capacitors to further increase energy density without sacrificing power. Conducting polymers work best in asymmetric configurations using different polymers or a polymer-carbon composite to expand the operating voltage window.
Lithium-ion batteries were first proposed in the 1970s but were not successfully created until the mid-1980s. The first commercial lithium-ion battery was launched by Sony in 1991. Lithium-ion batteries use lithium compounds in the anode and a lithium cobalt oxide or lithium iron phosphate cathode. During discharge, lithium ions move from the anode to the cathode and back during charging through an electrolyte. Lithium-ion batteries have a high energy density and output voltage, long cycle life, and are more environmentally friendly than alternatives. However, they are also more expensive and require temperature monitoring and sealing to prevent issues.
This document discusses supercapacitors, also known as ultracapacitors. It provides a brief history, noting they were first developed in 1957 and licensed for market production in 1978. Supercapacitors store energy electrostatically at the interface between an electrode and electrolyte through a double-layer capacitance effect. They have a higher power density than batteries but lower energy density. The document outlines the key components of a supercapacitor including polarized electrodes made of highly porous activated carbon, electrolytes that allow ion migration during charging and discharging, and separators that provide insulation between electrodes while allowing ion conduction. Applications mentioned include use in diesel engines, trains, power systems, and missiles to recover and deliver braking energy.
This document discusses supercapacitors, also known as electric double layer capacitors or ultracapacitors. It defines supercapacitors as electrochemical capacitors that can store much higher energy than common capacitors. The document outlines the basic design of supercapacitors, including their electrodes, electrolyte, and separator. It describes the three main types - electrochemical double layer capacitors, pseudocapacitors, and hybrid capacitors - and their charge storage mechanisms. Applications, advantages over batteries, and disadvantages of supercapacitors are also summarized.
Conducting polymers were discovered in the late 1970s and represent an important class of organic polymers that can conduct electricity. They become conductive through a process called doping, where their polymer chains take on charges. This allows for charge carriers called polarons and bipolarons to form, making the material conductive. Conducting polymers have advantages over traditional conductors including light weight, flexibility, and potential applications in areas like sensors, batteries, and displays. However, issues remain around their reproducibility, stability, processing difficulties, and high costs.
Chemical and electrochem method of synthesis of polyaniline and polythiophene...Mugilan Narayanasamy
This document summarizes chemical and electrochemical methods for synthesizing polyaniline and polythiophene. Polyaniline can exist in three oxidation states - leucoemeraldine, emeraldine, and pernigraniline. It can be synthesized chemically using an oxidative process with an acid and oxidizing agent like ammonium persulfate or potassium dichromate. Electrochemical synthesis grows a polyaniline film on an anode. Polythiophene is also synthesized chemically using oxidative polymerization with catalysts or electrochemically by applying a potential to drive polymerization. The McCullough and Rieke methods can produce regioregular polythiophene using nickel or palladium catalysts. Both polymers find applications in
Conducting polymers are those polymers which conduct electricity due to extended P- orbital system. Due to this extension of P orbital electrons can move from one end to another end of the polymer.
The document discusses nanomaterials used for electrodes in supercapacitors. It begins by explaining the basic construction and working of supercapacitors, which store charge electrostatically at the electrode-electrolyte interface. Common nanomaterial electrodes mentioned include activated carbon, carbon aerogel, graphene, and carbon nanotubes due to their high surface areas and conductivities. These properties allow for high capacitance and energy density in supercapacitors.
Conducting polymer based flexible super capacitors [autosaved]Jishana Basheer
Conducting polymers have potential in flexible supercapacitors due to their redox properties. Polyaniline, polypyrrole and polythiophene are promising conducting polymers. Graphene composites with these polymers improve performance by preventing aggregation and enabling fast ion transport. Future work aims to develop ternary composites and asymmetric capacitors to further increase energy density without sacrificing power. Conducting polymers work best in asymmetric configurations using different polymers or a polymer-carbon composite to expand the operating voltage window.
Lithium-ion batteries were first proposed in the 1970s but were not successfully created until the mid-1980s. The first commercial lithium-ion battery was launched by Sony in 1991. Lithium-ion batteries use lithium compounds in the anode and a lithium cobalt oxide or lithium iron phosphate cathode. During discharge, lithium ions move from the anode to the cathode and back during charging through an electrolyte. Lithium-ion batteries have a high energy density and output voltage, long cycle life, and are more environmentally friendly than alternatives. However, they are also more expensive and require temperature monitoring and sealing to prevent issues.
This document discusses supercapacitors, also known as ultracapacitors. It provides a brief history, noting they were first developed in 1957 and licensed for market production in 1978. Supercapacitors store energy electrostatically at the interface between an electrode and electrolyte through a double-layer capacitance effect. They have a higher power density than batteries but lower energy density. The document outlines the key components of a supercapacitor including polarized electrodes made of highly porous activated carbon, electrolytes that allow ion migration during charging and discharging, and separators that provide insulation between electrodes while allowing ion conduction. Applications mentioned include use in diesel engines, trains, power systems, and missiles to recover and deliver braking energy.
This document discusses supercapacitors, also known as electric double layer capacitors or ultracapacitors. It defines supercapacitors as electrochemical capacitors that can store much higher energy than common capacitors. The document outlines the basic design of supercapacitors, including their electrodes, electrolyte, and separator. It describes the three main types - electrochemical double layer capacitors, pseudocapacitors, and hybrid capacitors - and their charge storage mechanisms. Applications, advantages over batteries, and disadvantages of supercapacitors are also summarized.
Conducting polymers were discovered in the late 1970s and represent an important class of organic polymers that can conduct electricity. They become conductive through a process called doping, where their polymer chains take on charges. This allows for charge carriers called polarons and bipolarons to form, making the material conductive. Conducting polymers have advantages over traditional conductors including light weight, flexibility, and potential applications in areas like sensors, batteries, and displays. However, issues remain around their reproducibility, stability, processing difficulties, and high costs.
Chemical and electrochem method of synthesis of polyaniline and polythiophene...Mugilan Narayanasamy
This document summarizes chemical and electrochemical methods for synthesizing polyaniline and polythiophene. Polyaniline can exist in three oxidation states - leucoemeraldine, emeraldine, and pernigraniline. It can be synthesized chemically using an oxidative process with an acid and oxidizing agent like ammonium persulfate or potassium dichromate. Electrochemical synthesis grows a polyaniline film on an anode. Polythiophene is also synthesized chemically using oxidative polymerization with catalysts or electrochemically by applying a potential to drive polymerization. The McCullough and Rieke methods can produce regioregular polythiophene using nickel or palladium catalysts. Both polymers find applications in
Conducting polymers are those polymers which conduct electricity due to extended P- orbital system. Due to this extension of P orbital electrons can move from one end to another end of the polymer.
The document discusses nanomaterials used for electrodes in supercapacitors. It begins by explaining the basic construction and working of supercapacitors, which store charge electrostatically at the electrode-electrolyte interface. Common nanomaterial electrodes mentioned include activated carbon, carbon aerogel, graphene, and carbon nanotubes due to their high surface areas and conductivities. These properties allow for high capacitance and energy density in supercapacitors.
Nano-materials for Anodes in Lithium ion Battery - An introduction part 1Ahmed Hashem Abdelmohsen
The document discusses approaches to improving lithium ion battery anodes using nanomaterials. It provides a general introduction to lithium batteries and their components. Nanometal oxides like iron oxide nanoparticles coated on carbon aerogel are discussed as an anode material with high capacity and excellent cycleability. Nanostructured silicon anodes are also covered, which can provide high capacity due to silicon's ability to alloy with lithium at room temperature. Finally, graphene-coated pyrogenic carbon is presented as an anode material that provides a reversible high discharge capacity through the unique properties of graphene.
This document discusses advances in solid state batteries, including lithium-ion batteries and technologies beyond lithium-ion like sodium-ion batteries. It covers topics like the use of solid electrolytes instead of liquid electrolytes in lithium-ion batteries to improve safety and performance. The document also examines new cathode and anode materials that could enable higher energy densities in future battery technologies beyond lithium-ion, such as lithium-sulfur and lithium-air batteries. Research is ongoing to develop low-cost, sustainable batteries with improved cycle life, safety, and energy density for applications like electric vehicles.
This document provides an introduction to conducting polymers. It discusses how conducting polymers were discovered in the late 1970s and can be used as alternatives to metal conductors due to advantages like being light weight, flexible, and having non-metallic surface properties. Common conducting polymers include polyacetylene, polypyrrole, and polyaniline. The document outlines how conducting polymers are classified and the doping process used to increase their conductivity. Potential applications of conducting polymers discussed include coatings, sensors, biocompatible polymers, batteries, displays, and conductive adhesives.
The document summarizes research on modifying the bandgap of n-TiO2 through carbon doping to enable its use in photoelectrochemical water splitting using visible light. Carbon-modified n-TiO2 (CM-n-TiO2) films were synthesized using spray pyrolysis. Increased carbon doping was achieved by calcining in inert atmosphere. CM-n-TiO2 exhibited photoresponse in the visible spectrum due to carbon doping reducing the bandgap and introducing an intragap band. This modified the band structure of n-TiO2 to extend utilization of solar energy into the visible region.
Solid electrolytes for lithium ion solid state batteries patent landscape 201...Knowmade
Report’s Key Features
• PDF with > 250 slides
• Excel file > 5,800 patents
• IP trends, including time-evolution of published patents, legal status, countries of patent filings, etc.
• Ranking of main patent assignees
• Patent categorization by type of electrolyte (polymer, inorganic, inorganic/polymer) and inorganic electrolyte materials (sulfide glass ceramics, Thio-LISICON, argyrodite, oxide glass ceramics, NASICON, perovskite, garnet, anti-perovskite, hydride)
• For each technical segment: IP dynamics, ranking of main patent assignees, newcomers, key IP players (leadership, blocking potential, portfolio strength), key patents, and recent development trends
• For each key IP player (100+ companies): Time-evolution of patenting activity, legal status of patents and countries of patent filings, patent segmentation by electrolyte material, IP strengths and weaknesses by electrolyte material
• Excel database containing all patents analyzed in this report, including technology and material segmentations
Voltammetry involves applying a potential to a working electrode and measuring the resulting current. It can characterize redox reactions through parameters like peak potentials and currents in cyclic voltammetry. Cyclic voltammetry cycles the potential of a working electrode versus a reference electrode and measures the current. It is used to study redox processes and obtain information about reaction kinetics and mechanisms. The peak separation and shapes of cyclic voltammograms provide information about whether redox processes are reversible or irreversible.
ALL-SOLID STATE BATTERIES: AN OVERVIEW FOR BIO APPLICATIONSGururaj B Rawoor
This technical seminar overviewed all-solid state batteries and their applications for bio uses. It discussed the history of batteries from Galvani's discovery of "animal electricity" to Volta's invention of the first chemical battery. The seminar described the working principles of solid state batteries, which have solid electrodes and electrolytes, as well as their advantages over conventional lithium-ion batteries that use liquid electrolytes. Challenges for future batteries were presented, such as replacing the metallic lithium anode, and applications discussed including portable devices, electric vehicles, and medical implants.
The Materials Science of Lithium-Ion Batteries (Sept 2014)Andrew Gelston
The document discusses lithium-ion batteries and their materials. It provides an overview of lithium-ion battery components and chemistry, focusing on the commonly used 18650 battery cell format. Key points covered include the anode, cathode, and electrolyte materials used in lithium-ion batteries and how they enable the transfer of lithium ions and electrons. Degradation issues related to cycling and temperature are also summarized.
Nano solar cells utilize tiny nanorods or nanoparticles to convert sunlight into electricity in a thin, inexpensive layer. These dye-sensitized or "nano" solar cells consist of a thin layer of nanorods dispersed in a polymer that can be easily mass produced. While efficiency is still low, nano solar cells have potential for low-cost electricity generation due to inexpensive manufacturing using solution-based coating or printing techniques.
The presentation discusses the working principle and applications of fuel cells, the oxygen reduction reaction (ORR) in fuel cells, and various electrocatalysts used for ORR. It outlines the working principle of fuel cells, where hydrogen is oxidized at the anode to produce protons and electrons. At the cathode, oxygen reacts with protons and electrons to form water. Various electrocatalysts discussed that catalyze the ORR include platinum, carbon materials like graphite and nanotubes, transition metals and their compounds. The presentation provides details on the mechanisms of ORR on different catalysts and how doping or alloying can influence their activity.
This document discusses potential non-carbon anode materials for lithium ion batteries. It describes three categories of materials: 1) insertion materials like titanium oxides that store lithium through intercalation, 2) alloying materials like tin oxide that react with lithium in an alloying/dealloying mechanism, and 3) conversion materials like metal oxides and phosphides that undergo a conversion reaction with lithium. While these alternative anode materials offer higher capacities than graphite, the document notes that challenges remain like capacity fading and potential hysteresis that have prevented their widespread commercial use.
Water can be split into hydrogen and oxygen through various methods including electrolysis, photolysis, and photoelectrochemical water splitting. Water splitting produces hydrogen which can be used as a renewable fuel and reduces greenhouse gas emissions. Recent research has successfully used an artificial compound called Nafion to split water into hydrogen and oxygen through photoelectrochemical water splitting, demonstrating progress toward replicating natural photosynthesis and providing a clean energy source.
Conducting polymers are organic polymers that conduct electricity. They derive their conductivity from conjugated double bonds along the polymer backbone or aromatic rings connected by single bonds. Their conductivity can be enhanced through doping, which involves adding electrons or removing electrons through oxidation or reduction. This leads to the formation of polarons or bipolarons along the polymer chain, allowing for charge mobility. Common conducting polymers include polyacetylene, polyaniline, and polypyrrole. They find applications in rechargeable batteries, sensors, biomedical devices, solar cells, and electronic displays.
A dye sensitized solar cell (DSSC) functions by using light absorbing dye molecules to convert sunlight into electricity through photovoltaic processes. When light is absorbed by the dye, electrons are injected into the conduction band of a nanostructured titanium dioxide layer. The electrons then travel through an external circuit, generating electricity, and are collected by a counter electrode. The oxidized dye is regenerated by electron donation from an electrolyte, allowing the process to repeat continuously. DSSCs have the advantages of being relatively inexpensive, flexible in design, and using natural dyes, making them a promising solar technology.
This document discusses conducting polymers, which are polymers that conduct electricity. There are two types of conducting polymers: intrinsic and extrinsic. Intrinsic conducting polymers have conjugated double bonds in their backbone that allow for electron delocalization, while extrinsic polymers contain added conductive elements. Intrinsically, polymers can conduct due to thermal or light activation of electrons to overcome an energy gap (e.g. polyacetylene). Conductivity can also be increased through doping, which introduces positive or negative charges through oxidation or reduction of the polymer backbone. Conducting polymers have applications in rechargeable batteries, sensors, electronic devices, solar cells, and more.
The document discusses the design of new cathode materials for secondary lithium ion batteries. It provides background on the development of batteries over time and describes the basic components and operation of lithium ion batteries. Current commercially used cathode materials like lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, and lithium iron phosphate are described. Research aims to develop new cathode materials with improved properties like higher energy density, longer lifespan, lower cost, and environmental friendliness. Promising candidates include olivine-based phosphates and transition metal oxides.
Dye-sensitized solar cells (DSSCs) are a type of solar cell that uses dye molecules to absorb sunlight and convert it to electrical energy. They were invented in 1991 by Brian O'Regan and Michael Grätzel. DSSCs consist of a photo-sensitized anode, an electrolyte containing a redox couple, and a cathode. When light is absorbed by the dye, electrons are injected into the conduction band of the semiconductor and transported through the external circuit to be collected at the cathode, while the dye is regenerated through the redox shuttle. DSSCs offer advantages such as low cost, flexibility in design, and the ability to work in low light conditions. Recent research aims to
This document discusses lithium ion batteries with silicon anodes as an improvement over traditional graphite anodes. Silicon can store 10 times more lithium than graphite, offering higher energy density and capacity. However, silicon's large volume changes during charging cause cracking issues. Researchers are using silicon nanowires which can accommodate these changes without breaking. Silicon nanowire battery electrodes provide good performance with high capacity and long cycle life. Potential applications of lithium ion silicon anode batteries include consumer electronics, electric vehicles, and stationary energy storage.
This presentation includes all the information regarding polymer batteries, lithium polymer batteries. Including animations and transitions this PowerPoint presentation is enough for you to understand all about Polymer batteries and cells.
Liquid Electrolyte for Lithium BatteriesSaiful Islam
The document discusses liquid electrolytes for lithium-ion batteries. It describes the key requirements for liquid electrolytes including high ionic conductivity, chemical and electrochemical stability, ability to operate over a wide temperature range, safety, and low cost. The typical components of liquid electrolytes are organic solvents like ethylene carbonate and lithium salts like LiPF6. Additives are also discussed that can enhance properties like improving the solid electrolyte interphase layer formation and increasing ionic conductivity. The development of commonly used organic solvents and lithium salts over time is also summarized.
This document summarizes key concepts in chemistry that are relevant to understanding the chemical basis of life. It defines matter and its composition of elements and atoms. It describes the structure of atoms including protons, neutrons, electrons and electron shells. It explains the formation of molecules, compounds, and different types of chemical bonds. It discusses the unique properties of water and its role in biological systems. It also summarizes the main macromolecules that make up living things - carbohydrates, lipids, proteins and nucleic acids - and describes their structure and functions.
1. Atoms are the basic units of matter and consist of electrons, protons, and neutrons. Elements are composed of a single type of atom, which can have different isotopes depending on the number of neutrons.
2. Chemical bonds form when atoms share or transfer electrons to fill their outer electron shells. The four main types of bonds are covalent, ionic, hydrogen, and metallic bonds.
3. Chemical reactions involve the formation or breaking of chemical bonds to create new molecules. Key reactions include synthesis, decomposition, and exchange reactions.
Nano-materials for Anodes in Lithium ion Battery - An introduction part 1Ahmed Hashem Abdelmohsen
The document discusses approaches to improving lithium ion battery anodes using nanomaterials. It provides a general introduction to lithium batteries and their components. Nanometal oxides like iron oxide nanoparticles coated on carbon aerogel are discussed as an anode material with high capacity and excellent cycleability. Nanostructured silicon anodes are also covered, which can provide high capacity due to silicon's ability to alloy with lithium at room temperature. Finally, graphene-coated pyrogenic carbon is presented as an anode material that provides a reversible high discharge capacity through the unique properties of graphene.
This document discusses advances in solid state batteries, including lithium-ion batteries and technologies beyond lithium-ion like sodium-ion batteries. It covers topics like the use of solid electrolytes instead of liquid electrolytes in lithium-ion batteries to improve safety and performance. The document also examines new cathode and anode materials that could enable higher energy densities in future battery technologies beyond lithium-ion, such as lithium-sulfur and lithium-air batteries. Research is ongoing to develop low-cost, sustainable batteries with improved cycle life, safety, and energy density for applications like electric vehicles.
This document provides an introduction to conducting polymers. It discusses how conducting polymers were discovered in the late 1970s and can be used as alternatives to metal conductors due to advantages like being light weight, flexible, and having non-metallic surface properties. Common conducting polymers include polyacetylene, polypyrrole, and polyaniline. The document outlines how conducting polymers are classified and the doping process used to increase their conductivity. Potential applications of conducting polymers discussed include coatings, sensors, biocompatible polymers, batteries, displays, and conductive adhesives.
The document summarizes research on modifying the bandgap of n-TiO2 through carbon doping to enable its use in photoelectrochemical water splitting using visible light. Carbon-modified n-TiO2 (CM-n-TiO2) films were synthesized using spray pyrolysis. Increased carbon doping was achieved by calcining in inert atmosphere. CM-n-TiO2 exhibited photoresponse in the visible spectrum due to carbon doping reducing the bandgap and introducing an intragap band. This modified the band structure of n-TiO2 to extend utilization of solar energy into the visible region.
Solid electrolytes for lithium ion solid state batteries patent landscape 201...Knowmade
Report’s Key Features
• PDF with > 250 slides
• Excel file > 5,800 patents
• IP trends, including time-evolution of published patents, legal status, countries of patent filings, etc.
• Ranking of main patent assignees
• Patent categorization by type of electrolyte (polymer, inorganic, inorganic/polymer) and inorganic electrolyte materials (sulfide glass ceramics, Thio-LISICON, argyrodite, oxide glass ceramics, NASICON, perovskite, garnet, anti-perovskite, hydride)
• For each technical segment: IP dynamics, ranking of main patent assignees, newcomers, key IP players (leadership, blocking potential, portfolio strength), key patents, and recent development trends
• For each key IP player (100+ companies): Time-evolution of patenting activity, legal status of patents and countries of patent filings, patent segmentation by electrolyte material, IP strengths and weaknesses by electrolyte material
• Excel database containing all patents analyzed in this report, including technology and material segmentations
Voltammetry involves applying a potential to a working electrode and measuring the resulting current. It can characterize redox reactions through parameters like peak potentials and currents in cyclic voltammetry. Cyclic voltammetry cycles the potential of a working electrode versus a reference electrode and measures the current. It is used to study redox processes and obtain information about reaction kinetics and mechanisms. The peak separation and shapes of cyclic voltammograms provide information about whether redox processes are reversible or irreversible.
ALL-SOLID STATE BATTERIES: AN OVERVIEW FOR BIO APPLICATIONSGururaj B Rawoor
This technical seminar overviewed all-solid state batteries and their applications for bio uses. It discussed the history of batteries from Galvani's discovery of "animal electricity" to Volta's invention of the first chemical battery. The seminar described the working principles of solid state batteries, which have solid electrodes and electrolytes, as well as their advantages over conventional lithium-ion batteries that use liquid electrolytes. Challenges for future batteries were presented, such as replacing the metallic lithium anode, and applications discussed including portable devices, electric vehicles, and medical implants.
The Materials Science of Lithium-Ion Batteries (Sept 2014)Andrew Gelston
The document discusses lithium-ion batteries and their materials. It provides an overview of lithium-ion battery components and chemistry, focusing on the commonly used 18650 battery cell format. Key points covered include the anode, cathode, and electrolyte materials used in lithium-ion batteries and how they enable the transfer of lithium ions and electrons. Degradation issues related to cycling and temperature are also summarized.
Nano solar cells utilize tiny nanorods or nanoparticles to convert sunlight into electricity in a thin, inexpensive layer. These dye-sensitized or "nano" solar cells consist of a thin layer of nanorods dispersed in a polymer that can be easily mass produced. While efficiency is still low, nano solar cells have potential for low-cost electricity generation due to inexpensive manufacturing using solution-based coating or printing techniques.
The presentation discusses the working principle and applications of fuel cells, the oxygen reduction reaction (ORR) in fuel cells, and various electrocatalysts used for ORR. It outlines the working principle of fuel cells, where hydrogen is oxidized at the anode to produce protons and electrons. At the cathode, oxygen reacts with protons and electrons to form water. Various electrocatalysts discussed that catalyze the ORR include platinum, carbon materials like graphite and nanotubes, transition metals and their compounds. The presentation provides details on the mechanisms of ORR on different catalysts and how doping or alloying can influence their activity.
This document discusses potential non-carbon anode materials for lithium ion batteries. It describes three categories of materials: 1) insertion materials like titanium oxides that store lithium through intercalation, 2) alloying materials like tin oxide that react with lithium in an alloying/dealloying mechanism, and 3) conversion materials like metal oxides and phosphides that undergo a conversion reaction with lithium. While these alternative anode materials offer higher capacities than graphite, the document notes that challenges remain like capacity fading and potential hysteresis that have prevented their widespread commercial use.
Water can be split into hydrogen and oxygen through various methods including electrolysis, photolysis, and photoelectrochemical water splitting. Water splitting produces hydrogen which can be used as a renewable fuel and reduces greenhouse gas emissions. Recent research has successfully used an artificial compound called Nafion to split water into hydrogen and oxygen through photoelectrochemical water splitting, demonstrating progress toward replicating natural photosynthesis and providing a clean energy source.
Conducting polymers are organic polymers that conduct electricity. They derive their conductivity from conjugated double bonds along the polymer backbone or aromatic rings connected by single bonds. Their conductivity can be enhanced through doping, which involves adding electrons or removing electrons through oxidation or reduction. This leads to the formation of polarons or bipolarons along the polymer chain, allowing for charge mobility. Common conducting polymers include polyacetylene, polyaniline, and polypyrrole. They find applications in rechargeable batteries, sensors, biomedical devices, solar cells, and electronic displays.
A dye sensitized solar cell (DSSC) functions by using light absorbing dye molecules to convert sunlight into electricity through photovoltaic processes. When light is absorbed by the dye, electrons are injected into the conduction band of a nanostructured titanium dioxide layer. The electrons then travel through an external circuit, generating electricity, and are collected by a counter electrode. The oxidized dye is regenerated by electron donation from an electrolyte, allowing the process to repeat continuously. DSSCs have the advantages of being relatively inexpensive, flexible in design, and using natural dyes, making them a promising solar technology.
This document discusses conducting polymers, which are polymers that conduct electricity. There are two types of conducting polymers: intrinsic and extrinsic. Intrinsic conducting polymers have conjugated double bonds in their backbone that allow for electron delocalization, while extrinsic polymers contain added conductive elements. Intrinsically, polymers can conduct due to thermal or light activation of electrons to overcome an energy gap (e.g. polyacetylene). Conductivity can also be increased through doping, which introduces positive or negative charges through oxidation or reduction of the polymer backbone. Conducting polymers have applications in rechargeable batteries, sensors, electronic devices, solar cells, and more.
The document discusses the design of new cathode materials for secondary lithium ion batteries. It provides background on the development of batteries over time and describes the basic components and operation of lithium ion batteries. Current commercially used cathode materials like lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, and lithium iron phosphate are described. Research aims to develop new cathode materials with improved properties like higher energy density, longer lifespan, lower cost, and environmental friendliness. Promising candidates include olivine-based phosphates and transition metal oxides.
Dye-sensitized solar cells (DSSCs) are a type of solar cell that uses dye molecules to absorb sunlight and convert it to electrical energy. They were invented in 1991 by Brian O'Regan and Michael Grätzel. DSSCs consist of a photo-sensitized anode, an electrolyte containing a redox couple, and a cathode. When light is absorbed by the dye, electrons are injected into the conduction band of the semiconductor and transported through the external circuit to be collected at the cathode, while the dye is regenerated through the redox shuttle. DSSCs offer advantages such as low cost, flexibility in design, and the ability to work in low light conditions. Recent research aims to
This document discusses lithium ion batteries with silicon anodes as an improvement over traditional graphite anodes. Silicon can store 10 times more lithium than graphite, offering higher energy density and capacity. However, silicon's large volume changes during charging cause cracking issues. Researchers are using silicon nanowires which can accommodate these changes without breaking. Silicon nanowire battery electrodes provide good performance with high capacity and long cycle life. Potential applications of lithium ion silicon anode batteries include consumer electronics, electric vehicles, and stationary energy storage.
This presentation includes all the information regarding polymer batteries, lithium polymer batteries. Including animations and transitions this PowerPoint presentation is enough for you to understand all about Polymer batteries and cells.
Liquid Electrolyte for Lithium BatteriesSaiful Islam
The document discusses liquid electrolytes for lithium-ion batteries. It describes the key requirements for liquid electrolytes including high ionic conductivity, chemical and electrochemical stability, ability to operate over a wide temperature range, safety, and low cost. The typical components of liquid electrolytes are organic solvents like ethylene carbonate and lithium salts like LiPF6. Additives are also discussed that can enhance properties like improving the solid electrolyte interphase layer formation and increasing ionic conductivity. The development of commonly used organic solvents and lithium salts over time is also summarized.
This document summarizes key concepts in chemistry that are relevant to understanding the chemical basis of life. It defines matter and its composition of elements and atoms. It describes the structure of atoms including protons, neutrons, electrons and electron shells. It explains the formation of molecules, compounds, and different types of chemical bonds. It discusses the unique properties of water and its role in biological systems. It also summarizes the main macromolecules that make up living things - carbohydrates, lipids, proteins and nucleic acids - and describes their structure and functions.
1. Atoms are the basic units of matter and consist of electrons, protons, and neutrons. Elements are composed of a single type of atom, which can have different isotopes depending on the number of neutrons.
2. Chemical bonds form when atoms share or transfer electrons to fill their outer electron shells. The four main types of bonds are covalent, ionic, hydrogen, and metallic bonds.
3. Chemical reactions involve the formation or breaking of chemical bonds to create new molecules. Key reactions include synthesis, decomposition, and exchange reactions.
The document provides an overview of key concepts in biochemistry and cell chemistry, including:
1) It discusses the four main classes of biomolecules - proteins, nucleic acids, carbohydrates, and lipids - and how cells require these molecules to carry out functions and maintain structure.
2) It explains the importance of water for living organisms and describes water's chemical properties that allow it to act as a solvent.
3) It summarizes the structures of important biomolecules like carbohydrates, proteins, and nucleic acids and how they are synthesized through polymerization of monomers.
This chapter discusses the chemical level of organization of the human body. It covers the basic units that make up all matter - elements, atoms, and molecules. The structures and types of four major biomolecules - carbohydrates, lipids, proteins, and nucleic acids - are summarized. Key chemical processes like metabolism and catalysis by enzymes are also introduced.
The document discusses various topics related to polymers including their classification, types, mechanisms of polymerization, and methods of polymerization. Polymers can be classified based on their chain structure, chemical composition, source, and backbone. The main types are thermoplastics, thermosets, and elastomers. Polymerization can occur via addition or condensation reactions and methods include bulk, solution, suspension, and emulsion polymerization.
The document discusses various topics related to polymers including their classification, types, mechanisms of polymerization, and polymerization reactions. It classifies polymers based on their chain structure, chemical composition, source, and backbone. The main types discussed are thermoplastics, thermosets, and elastomers. It describes the mechanisms of condensation and addition polymerization. Chain polymerization reactions like free radical, anionic and cationic polymerization are explained in detail with their initiation, propagation and termination steps.
SYNTHESIS AND CHARACTERIZATION OF CONDUCTING POLYMERS: A REVIEW PAPERpaperpublications3
Abstract: Polymers are long chains of repeating chemical units called monomers. They share several characteristics including macro and micro properties, electrical transport properties, semiconducting properties and optical properties. Polymers can be synthesized by chemical and electrochemical polymerization. Polymers prepared through these methods can also be characterized by their electrical, optical, mechanical and electrochemical means.
Encyclopedia of physical science and technology polymers 2001PaReJaiiZz
This document provides a table of contents for an encyclopedia on physical science and technology. It lists 14 articles related to polymers, including biopolymers, macromolecules, plastics engineering, polymer processing, and polymers with various electronic, mechanical, photoresponsive, and thermal properties. Each article is 1-3 pages long and provides information on a specific topic within the subject area of polymers.
he reaction involving combination of two or more monomer units to form a long chain polymer is termed as polymerization. These are widely used as Pharmaceutical aids like suspending agents, Emulsifying agents, Adhesives, Coating agents, Adjuvants etc.
Catalytic polymerization and types of polymerizationshaizachandoor
Its about the catalytic polymerization.
Its tells the types of the catalytic polymerization and about the Ziegler natta polymerization .
It has the details of co-odination polymerization and addition polymerization and their further types.
It is easy to access and has a proper guidelines for the students to look and study and easy to understand.
The document discusses key concepts in chemistry and biology. It defines atoms, elements, compounds, and chemical bonds. The four most common elements in living things are carbon, hydrogen, oxygen, and nitrogen. Compounds are formed when elements combine. Chemical reactions involve rearranging atoms. Enzymes are biological catalysts that speed up reactions. Water is a polar solvent that hydrates polar molecules. Solutions are uniform mixtures, while suspensions and colloids are not. Macromolecules like carbohydrates, lipids, proteins, and nucleic acids are made of repeating subunits and perform important functions in living things.
SYNTHESIS AND CHARACTERIZATION OF CONDUCTING POLYMERS: A REVIEW PAPERpaperpublications3
This document reviews the synthesis and characterization of conducting polymers. It discusses how conducting polymers can be synthesized through chemical or electrochemical polymerization of monomers like polyacetylene, polypyrrole, and polythiophene. The polymers are then characterized using various electrical, mechanical, and electrochemical techniques. The key features of electrochemical polymerization are that doping and processing occur simultaneously during synthesis. Conducting polymers find applications in areas like batteries, LEDs, sensors due to their electrical and optical properties, which can be precisely controlled through doping. In conclusion, conducting polymers are promising for applications like solar energy cells due to their light weight and low-cost fabrication compared to metals.
1.1 Introduction
1.2 Classification of Complexation
1.3 Applications, Methods of Analysis
1.4 Protein Binding
1.5 Complexation and the drug actions
1.6 Crystalline Structures of Complexes and Thermodynamic Treatment of Stability Constants.
The document discusses the key components that make up living organisms on a molecular level. It defines atoms, molecules, and macromolecules like carbohydrates, lipids, proteins, and nucleic acids. It explains how chemical reactions and molecular bonding allow these components to assemble into larger structures that carry out life processes. pH and electrolytes are also summarized in relation to their importance in human physiology.
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Polymer electrolytes and fuel cells
1. POLYMER ELECTROLYTES AND FUEL
CELLS
APPLIED ASPECTS OF BIOTECHNOLOGY
SHARAVANAKKUMAR SK
III B.Sc. BIOTECHNOLOGY
PSG COLLEGE OF ARTS AND SCIENCE
2. Electrolytic Cell
An electrolytic cell is an electrochemical cell that drives a non-
spontaneous redox reaction through the application of electrical
energy. They are often used to decompose chemical compounds, in a
process called electrolysis.
An electrolytic cell has three components,
Electrolyte
Cathode(Positive electrode)
Anode(Negative electrode)
Figure: A typical electrolytic cell
3. w
Electrolyte:
An electrolyte is a substance that produces an electrically
conducting solution when dissolved in a polar solvent, such
as water. The dissolved electrolyte separates into cations and
anions, which disperse uniformly through the solvent.
Electrically, such a solution is neutral.
Electrodes:
An electrode is a solid electric conductor that carries electric
current into non-metallic solids, or liquids, or gases, or
plasmas, or vacuums. Electrodes are typically good electric
conductors, but they need not be metals.
Types:
1.Classical liquid electrolytes
2.Gel electrolytes
3.Dry polymer electrolytes
4.Dry single-ion-conducting polymer electrolytes
5.Solvated single-ion-conducting polymer electrolytes
4. Polymer Electrolyte
Polymer electrolytes are very similar to the non-aqueous
electrolytes in general chemical makeup; however, instead of
using a liquid the lithium salts are dissolved into a polymer
gel matrix.
A polymer electrolyte is also referred to as a solid solvent that
possesses ion transport properties similar to that of the
common liquid ionic solution.
It usually comprises a polymer matrix and electrolyte,
wherein the electrolyte such as a lithium salt dissolves in a
polymer matrix.
polymer electrolytes are mainly used in electrochemical
devices such as batteries, electro-chromic devices, solar cells,
and super capacitors.
5. Properties
Polymer electrolytes are potential materials for solving the
never-ending demand for high energy density in energy devices.
Polymer electrolytes are defined as linear macromolecular
chains bearing a large number of charged or chargeable groups
when dissolved in a suitable solvent.
Polymer molecules that have one or a few ionic groups, in most
cases terminal and anionic, are called macroions.
These are primarily living polymers wherein polymer molecules
that are present in a polymerizing reaction system grow as long
as monomers (e.g., esters or nitriles of metha-crylic acid) are
continuously supplied.
The ionic charge of the macroions gets transferred to the next
monomer added, and this process continues by keeping the
macroions charged for the addition of further monomers.
6. w
Polymers having a considerable number of ionic groups and a
relatively nonpolar backbone are known as ionomers.
Those polymers with a number of ionic groups and that can
dissolve in water are known as polyelectrolytes.
Polymers with a much higher number of ionic groups get cross-
linked or undergo three-dimensional polymerization, which
constitutes the technically important group of ion exchangers.
To act as a successful polymer host, a polymer or the active part of
a copolymer should generally have a minimum of three essential
characteristics:
1.Atoms or groups of atoms with sufficient electron-donating power
to form coordinate bonds with cations.
2.Low barriers to bond rotation so that the segmental motion of the
polymer chain can take place readily.
3.A suitable distance between coordinating centers because the
formation of multiple intra-polymer ion bonds appears to be
important.
7. Bio-Polymer Electrolytes
The development of new materials that can be applied as solid
electrolytes has led to the creation of modern systems of energy
generation and storage.
Among different poly (ethylene oxide)-based electrolytes,
natural polymers, such as hydroxyethylcellulose,
hydroxypropylcellulose or carboxymethylcellulose
(polysaccharides), starch, polyvinyl alcohol, polyethylene glycol,
and chitosan or proteins such as gelatin are considered polymer
electrolytes.
Those polymers can undergo biodegradation as well as show the
ionic conductivity improvement by inorganic dopants, acids,
and gelation; these polymer electrolytes are called biopolymer
electrolytes.
Some natural biopolymer electrolytes that are widely used in
research are chitosan, starch, and cellulose materials.
The existence of polar groups in biopolymers is necessary to
dissolve salts and form stable ion-biopolymer complexes.
8. Types
Classification based on the sources and origins:
1.Synthetic biopolymer electrolytes based on bio-derived
monomers
e.g. Poly-(lactic acid)
2.Natural biopolymer electrolytes
e.g. Polysaccharides, Proteins.
Biopolymers from microbial fermentation
e.g. Polyhydroxybutyate, Hyaluronic acid, poly-γ-glutamic acid
Classification based on their physical state and composition:
1. Gel biopolymer electrolytes
2. Hydrogel biopolymer electrolytes
3. Solid biopolymer electrolytes
4. Blend biopolymer electrolytes
5. Composite polymer electrolytes
9. Dopants
Dopants are materials added with the biopolymers to increase
the conductivity of electrons in the electrolyte.
Lithium Salts as Dopants in Biopolymer:
Lithium salts have to completely dissolve in the applied
solvent at the optimized concentration and ions should be
able to transfer through the biopolymer matrix.
Lithium ions should not undergo oxidative decomposition at
the cathode.
Lithium ions must be inert to the electrolyte solvent/
biopolymer.
Both anion and cation should be inert toward other cell
components.
The anion must be nontoxic and remain thermally stable at
the energy device’s working conditions.
e.g. LiClO4, LiPF6, LiBF4, LiAsF6, LiCF3SO3, LiN(CF3O2)2
LiC(CF3SO2)2.
10. 2
Acids as Dopants in Biopolymer Electrolytes:
The advantage of proton-conducting biopolymer gel systems
consisting of H2SO4, o-H3PO4, and HCl in comparison with
lithium salt-doped polymer electrolytes arises from their
potentially higher conductivity and smaller ionic radius.
Furthermore, with biopolymer complexes with low inorganic
salt concentrations, ion pairing is possible, while at high
concentration the formation of large ionic aggregation may
occur.
Thus, lithium salts containing polymer electrolytes lack
higher power density and mainly depend upon electron-rich
functional groups of polymers for higher conductivity.
e.g. H3PO4 is a proton conductor in poly(ethylene amine),
poly(vinyl alcohol), poly(silamine)chitosan or iota-
carrageenan.
11. 2
Alkaline Dopants in Polymer Electrolytes:
Alkaline dopants are generally the salts containing OH–ions, the
involvement of OH ions in the conduction via hyper-coordinated
or per-solvated complexes.
e.g. KOH, Tetra-alkyl-ammonium hydroxide (TAAOH)
Plasticizing Salts or Ionic Liquids:
Ionic liquids are low-temperature molten salts. They consist of a
large cation and a charge-delocalized anion. These ionic liquids
are similar to organic electrolytes and can have vapor pressure up
to 250–450°C. The presence of organic ions provides unlimited
structural variations.12Biopolymer Electrolytes
Plasticizers are used to reduce the crystalline phase of polymer
and increase the ambient temperature ionic conductivity in
polymer-salt complexes.
e.g. Imidazolium, Pyrrolidinium, Quaternary ammonium salts,
Bis(trifluoromethanesulphonyl)imide, Bis(fluoro-sulphonyl)imide,
and Hexafluorophosphate.
12. SOLID BIOPOLYMER ELECTROLYTES (SBPE)
Solid biopolymer electrolytes are a liquid-free, high molecular
weight, polar polymer host having an ionically conducting
phase formed by dissolving salts.
Many polymer electrolyte materials will exhibit to a greater or
lesser extent the following properties:
Adequate conductivity for practical purposes
Good mechanical properties
Chemical, electrochemical, and photochemical stability
No possibility of leakage
Ease of processing
Shape flexibility
Lowering the cell weight-nonvolatile, all-solid-state cells do
not need a heavy steel casing
13. BLEND BIOPOLYMER ELECTROLYTES (BBPE)
BBPEs are a physical mixture of two or more polymer chains
forming a homogeneous (liquid) solvent-free system.
Sometimes, though the various phases are chemically bonded
together wherein the ionically conducting phase is formed by
dissolving inorganic salts.
Hydrogen bonding, charge transfer interactions, and dipole-
dipole forces form the basis for the miscibility of polymer blends.
The manifestation of properties of polymer blends depends upon
the miscibility of the components and structure.
14. q
Based on the fact that the polymers are compatible or miscible
they are classified:
1.Compatible blend: A mixture of polymer in which the overall
property is enhanced when compared with its non-blend
components. Herein, there are only physical forces of attraction
that keep the polymers in single phase.
2.Incompatible blend: A mixture of polymers in which the overall
property is less when compared with its non-blend components.
3.Polymer alloys: Compatibilizers are used to improve the
property balance these blends are commercial polymer blends
having interface.
4.Miscible blend: A mixture of polymers in which a homogenous
phase exists at a microscopic level due to physical forces and
hydrogen bonding.
Preparation of Polymer Blends:
1.Solution mixing-laboratory or paint industry, but the problem
is removing a solvent.
2.Interpenetrating networks-cross linked materials.
3.Melt mixing (physical, reactive)-most important method in
15. Gel Biopolymer electrolytes (GBPE)
GBPE is often known as a plasticized polymer electrolyte that
is neither liquid nor solid, or conversely both liquid and solid.
Gel contains a solid skeleton of polymers or long-chain
molecules cross-linked intra-molecularly or inter-molecularly,
entrapping an uninterrupted liquid phase.
The chemical composition and other factors such as hydrogen
bonding vary the chemistry of gels from viscous fluid to
moderately rigid solids.
Nevertheless, they are very soft and stretchy or “jelly like.”
Due to a large number of liquids filled in microspores most
gel materials exhibit liquid like characteristics microscopically,
but macroscopically have solid character.
The presence of the ultra-porous structure in the gel system
is likely to provide channels for ion migration.
16. Polymer electrolyte membrane fuel cells
Polymer electrolyte fuel cells are electrochemical devices,
converting the chemical energy of fuel directly into electrical
energy.
The working principle of PEFCs is based on the anode-
oxidation of hydrogen (fuel) to protons:
H2 → 2H+ + 2e−
The reduction of oxygen to water at the cathode:
4H+ + O2 + 4e− → 2H2O
Based on the thermodynamic data of the reactions, the
theoretical cell voltage is calculated via:
U= −ΔGnF
With the Gibbs free energy of the electrochemical reactions
Δ G, the number of the electrons n and the Faraday constant
F. At 25°C, the theoretical hydrogen/oxygen fuel cell voltage
is 1.23 V.
18. Components
PEMFCs are built out of membrane electrode assemblies
(MEA) which include the electrodes, electrolyte, catalyst, and
gas diffusion layers.
An ink of catalyst, carbon, and electrode are sprayed or
painted onto the solid electrolyte and carbon paper is hot
pressed on either side to protect the inside of the cell and
also act as electrodes.
The pivotal part of the cell is the triple phase boundary (TPB)
where the electrolyte, catalyst, and reactants mix and thus
where the cell reactions actually occur.
Importantly, the membrane must not be electrically
conductive so the half reactions do not mix.
Operating temperatures above 100 °C are desired so the
water byproduct becomes steam and water management
becomes less critical in cell design.
19. Electrolyte Membrane
To function, the membrane must conduct hydrogen ions
(protons) but not electrons as this would in effect "short circuit"
the fuel cell.
The membrane must also not allow either gas to pass to the
other side of the cell, a problem known as gas crossover.
Finally, the membrane must be resistant to the reducing
environment at the cathode as well as the harsh oxidative
environment at the anode.
Splitting of the hydrogen molecule is relatively easy by using a
platinum catalyst. However, splitting the oxygen molecule is
more difficult, and this causes significant electric losses.
An appropriate catalyst material for this process has not been
discovered, and platinum is the best option.
A cheaper alternative to platinum is Cerium(IV) oxide catalyst
used by the research group of professor Vladimir Matolín in the
development of PEMFC.
21. Electrodes
An electrode typically consists of carbon support, Pt particles,
Nafion ionomer, and/or Teflon binder.
The carbon support functions as an electrical conductor; the
Pt particles are reaction sites; the ionomer provides paths for
proton conduction.
Teflon binder increases the hydrophobicity of the electrode
to minimize potential flooding.
Gas diffusion layer
The GDL electrically connects the catalyst and current
collector. It must be porous, electrically conductive, and thin.
The reactants must be able to reach the catalyst, but
conductivity and porosity can act as opposing forces.
Optimally, the GDL should be composed of about one third
Nafion or 15% PTFE.
The carbon particles used in the GDL can be larger than
those employed in the catalyst because surface area is not
the most important variable in this layer.
GDL should be around 15–35 µm thick to balance needed
porosity with mechanical strength.
22. Efficiency
The maximal theoretical efficiency applying the Gibbs free
energy equation ΔG = −237.13 kJ/mol and using the heating
value of Hydrogen (ΔH = −285.84 kJ/mol) is 83% at 298 K.
η = Δ G /Δ H = 1 − [T Δ S /Δ H]
The practical efficiency of a PEMs is in the range of 50–60% .
Main factors that create losses are:
Activation losses
Ohmic losses
Mass transport losses
23. Applications
PEM fuel cells focuses on transportation primarily because of
their potential impact on the environment
e.g. the control of emission of the green house gases (GHG)
Distributed or stationary and portable power generation.
Most major motor companies work solely on PEM fuel cells
due to their high power density and excellent dynamic
characteristics as compared with other types of fuel cells.
Light weight and PEMFCs for buses, which use compressed
hydrogen for fuel, can operate at up to 40% efficiency.
PEM fuel cells were used in the NASA Gemini series of
spacecraft, but they were replaced by Alkaline fuel cells in the
Apollo program and in the Space shuttle.
Toyota Mirai, a car model which uses the PEMFCs are
produced and yet to be launched in the market.
24. References
Tokiwa Y, Suzuki T, Tokiwa Y, Suzuki T. Hydrolysis of polyesters by lipase.
Nature1977;270:76–8.
Gross RA, Kumar KB. Polymer synthesis by in vitro enzyme catalysis. Chem-
Rev2001;101:2097–124.
Mao H, Reamers JN, Jhong Q, von Sacken U. Proceedings of the
symposium on rechargeable lithium and lithium ion batteries, 94, 245, the
electrochemical society proceeding series, Pennington, NJ; 1995.
Uma T, Mahalingam T, Stimming U. Conductivity studies on poly(methyl
methacrylate)-Li2SO4polymer electrolyte systems. Mater Chem-Phys 2005;
90:245–9.
Stephan AM, Saito Y, Manuel Stephan A, Saito Y. Ionic conductivity and
diffusion coefficient studies of PVdF–HFP polymer electrolytes prepared
using phase inversion technique. Solid-State Ionics 2002;148:475–81.
Loyselle, Patricia; Prokopius, Kevin. "Teledyne Energy Systems, Inc., Proton
Exchange Member (PEM) Fuel Cell Engineering Model Power-plant. Test
Report: Initial Benchmark Tests in the Original Orientation". NASA. Glenn
Research Center. hdl:2060/20110014968.