Mitsunobu - Status of KEK Studies of Superconducting Thin Films by Pulsed La...thinfilmsworkshop
http://www.surfacetreatments.it/thinfilms
Status of KEK studies on MgB2 (Shinji Mitsunobu - 20')
Speaker: Shinji Mitsunobu - KEK | Duration: 20 min.
Abstract
We have been engaged in fabrication of high-Tc or MgB thin films on
metallic substrates. At the international workshop on thin films in
Padova, we showed our basic idea to make an accelerating-mode cavity.
In the last of this paper, we report a subsequent development, mainly a
partial success in fabricating superconducting film on a quadrant
cavity of an accelerator structure. In the beginning, we describe some
results concerning fabrication of films on Niobium and Titanium
surfaces.
Studies of Nb and Nb3Sn thin films by PLD will be shown.
Anne marie valente feliciano - nucleation of nb films on cu substratesthinfilmsworkshop
In the pursuit of niobium (Nb) films with similar performance with the commonly used bulk Nb surfaces for Superconducting RF (SRF) applications, significant progress has been made with the development of energetic condensation deposition techniques. The controlled incoming ion energy enables a number of processes such as desorption of adsorbed species, enhanced mobility of surface atoms and sub-implantation of impinging ions, thus producing improved film structures at lower process temperatures. All these along with the quality of the Cu substrate have an important influence on the nucleation and subsequent growth of the Nb film, creating a favorable template for growing the final surface exposed to SRF fields. This contribution shows how the structure and defect density thus electron mean free path (represented by residual resistance ratio values) of Nb films can be tailored on Cu substrates, by varying the ion energy and thermal energy provided to the substrate, favoring the hetero-epitaxial or the fiber growth mode.
Mitsunobu - Status of KEK Studies of Superconducting Thin Films by Pulsed La...thinfilmsworkshop
http://www.surfacetreatments.it/thinfilms
Status of KEK studies on MgB2 (Shinji Mitsunobu - 20')
Speaker: Shinji Mitsunobu - KEK | Duration: 20 min.
Abstract
We have been engaged in fabrication of high-Tc or MgB thin films on
metallic substrates. At the international workshop on thin films in
Padova, we showed our basic idea to make an accelerating-mode cavity.
In the last of this paper, we report a subsequent development, mainly a
partial success in fabricating superconducting film on a quadrant
cavity of an accelerator structure. In the beginning, we describe some
results concerning fabrication of films on Niobium and Titanium
surfaces.
Studies of Nb and Nb3Sn thin films by PLD will be shown.
Anne marie valente feliciano - nucleation of nb films on cu substratesthinfilmsworkshop
In the pursuit of niobium (Nb) films with similar performance with the commonly used bulk Nb surfaces for Superconducting RF (SRF) applications, significant progress has been made with the development of energetic condensation deposition techniques. The controlled incoming ion energy enables a number of processes such as desorption of adsorbed species, enhanced mobility of surface atoms and sub-implantation of impinging ions, thus producing improved film structures at lower process temperatures. All these along with the quality of the Cu substrate have an important influence on the nucleation and subsequent growth of the Nb film, creating a favorable template for growing the final surface exposed to SRF fields. This contribution shows how the structure and defect density thus electron mean free path (represented by residual resistance ratio values) of Nb films can be tailored on Cu substrates, by varying the ion energy and thermal energy provided to the substrate, favoring the hetero-epitaxial or the fiber growth mode.
Pd-Substituted (La,Sr)CrO3 for Solid Oxide Fuel Cell AnodesEmmaReneeDutton
Presentation of independent honors research thesis (June 2011) for Bachelor of Science in Materials Science & Engineering at Northwestern University.
Phillips - Atomic Layer Deposition of NbN Thin Films for Superconducting Radi...thinfilmsworkshop
http://www.surfacetreatments.it/thinfilms
Atomic Layer Deposition of NbN thin films for SRF applications (Larry Phillips - 15')
Speaker: Larry Phillips - Jefferson Lab - Newport News - Virginia | Duration: 15 min.
Abstract
Niobium Nitride is a 17K superconductor investigated since early eighthies for Superconducting Radiofrequency applications.
Atomic Layer deposition is instead a technique that only recently starts to be considered for industrial applications.
CMOS FABRICATION
For less power dissipation requirement CMOS technology is used for implementing transistors. If we require a faster circuit then transistors are implemented over IC using BJT . Fabrication of CMOS transistors as IC’s can be done in three different methods.
The N-well / P-well technology, where n-type diffusion is done over a p-type substrate or p-type diffusion is done over n-type substrate respectively.
P-WELL PROCESS
The fabrication steps of p well process are same as that of an n-well process except that instead of n-well a p-well is implanted . The process steps involved in p-well process are shown in Figure below. The process starts with the n type substrate
Mn impurities in CaZnOS: insight from luminescence spectroscopy and DFTJonas Joos
CaZnOS:Mn2+ is a rare-earth-free luminescent compound with an orange broadband emission at 612 nm, featuring pressure sensing capabilities, often explained by defect levels where energy can be stored. Despite recent efforts from experimental and theoretical point of view, the underlying luminescence mechanisms in this phosphor still lack a profound understanding. By evaluation of the thermoluminescence as function of the charging wavelength, we probe the defect levels allowing the energy storage. Multiple trap depths and trapping routes are found, suggesting predominantly local trapping close to the Mn2+ impurity. We demonstrate that this phosphor shows mechanoluminescence which is unexpectedly stable at high temperature (up to 200°C), allowing pressure sensing in a wide temperature range. Next, we correlate the spectroscopic results with a theoretical study of the electronic structure and stability of the Mn defects in CaZnOS. DFT calculations at PBE+U level indicate that the Mn impurity is incorporated on the Zn site in a divalent charge state, which is confirmed by x-ray absorption spectroscopy (XAS). A ligand-to-metal charge transfer (LMCT) is predicted from the location of the Mn impurity levels, obtained from the calculated defect formation energies. This LMCT proves to be a very efficient pathway for the energy storage. The excited state landscape of the Mn2+ 3d5 electron configuration is assessed through the spin-correlated crystal field and a good correspondence with the emission and excitation spectra is found. In conclusion, studying phosphors at both a single-particle level (i.e. via calculation of defect formation energies) and a many-particle level (i.e. by accurately localizing the excited states) is necessary to obtain a complete picture of luminescent defects, as demonstrated in the case of CaZnOS:Mn2+.
Potentiostatic Deposition of ZnO Nanowires: Effect of Applied Potential and Z...IJRES Journal
In this work we report on potentiostatic deposition of Zinc oxide (ZnO) nanowires on fluorine-doped tin oxide (FTO) covered glass substrates from electroreduction of molecular oxygen. The influence of applied deposition potential, and the concentrations of zinc precursor (ZnCl2) on the properties of ZnO nanowires was investigated.SEM results revealed that ZnO nanowires electrodeposited at applied potential -0.85Vhave high density and good alignment. The diameters and densities of the electrodeposited ZnO nanowires are strongly dependent on the zinc ion concentrations and well aligned nanowires with uniform diameter can be obtained when the concentration of zinc ions is between 0.5 mM and 1 mM.
Introduction to nanoscience and nanotechnologyaimanmukhtar1
Introduction of nanoscience/nanotechnology ,properties/potential applications of nanomaterials and electrodeposition of metal single component and alloy nanowires in AAO template
Enzo palmieri experimental results on thermal boundary resistance for niobi...thinfilmsworkshop
Unless of a few eclectic scientists that have studied the problem of Kapitza resistance, a superconducting cavity is almost always seen as an adiabatic system of the electromagnetic fields interacting with a Niobium sheet cooled at 4,2K or at temperatures between 1,8K and 2 K. In this talk it will be shown that the real system to consider is that of Electromagnetic fields, Niobium and liquid Helium.
And liquid Helium is a component much more complex than an infinite heat exchanger at fixed temperature. Even at superfluid temperatures indeed, at the interface between Helium and the superfluid, it will be always a nanometric thick layer of normal helium and the thickness of this layer depends on the RF power.
Niobium sputtered cavities will be also examined under the point of view of thermal boundary Resistance, arriving to the conclusion that more advanced comprehension of SRF cannot prescind from a deep understanding of Cryogenics
Sarah aull secondary electron yield of srf materialsthinfilmsworkshop
In the quest of new materials for SRF applications, the secondary electron yield (SEY) needs also to be taken into consideration. A high SEY holds the risk that multipacting becomes again a main performance limitation of an SRF cavity. In the worst case, a too high SEY makes a material completely unsuitablefor an RF exposed surface. This talk will discuss general aspects of the role of the surface condition and present SEY measurements on different SRF relevant materials, i.e. MgB2, Nb3Sn and NbTiN.
Sarah aull secondary electron yield of srf materialsthinfilmsworkshop
In the quest of new materials for SRF applications, the secondary electron yield (SEY) needs also to be taken into consideration. A high SEY holds the risk that multipacting becomes again a main performance limitation of an SRF cavity. In the worst case, a too high SEY makes a material completely unsuitablefor an RF exposed surface. This talk will discuss general aspects of the role of the surface condition and present SEY measurements on different SRF relevant materials, i.e. MgB2, Nb3Sn and NbTiN.
Pd-Substituted (La,Sr)CrO3 for Solid Oxide Fuel Cell AnodesEmmaReneeDutton
Presentation of independent honors research thesis (June 2011) for Bachelor of Science in Materials Science & Engineering at Northwestern University.
Phillips - Atomic Layer Deposition of NbN Thin Films for Superconducting Radi...thinfilmsworkshop
http://www.surfacetreatments.it/thinfilms
Atomic Layer Deposition of NbN thin films for SRF applications (Larry Phillips - 15')
Speaker: Larry Phillips - Jefferson Lab - Newport News - Virginia | Duration: 15 min.
Abstract
Niobium Nitride is a 17K superconductor investigated since early eighthies for Superconducting Radiofrequency applications.
Atomic Layer deposition is instead a technique that only recently starts to be considered for industrial applications.
CMOS FABRICATION
For less power dissipation requirement CMOS technology is used for implementing transistors. If we require a faster circuit then transistors are implemented over IC using BJT . Fabrication of CMOS transistors as IC’s can be done in three different methods.
The N-well / P-well technology, where n-type diffusion is done over a p-type substrate or p-type diffusion is done over n-type substrate respectively.
P-WELL PROCESS
The fabrication steps of p well process are same as that of an n-well process except that instead of n-well a p-well is implanted . The process steps involved in p-well process are shown in Figure below. The process starts with the n type substrate
Mn impurities in CaZnOS: insight from luminescence spectroscopy and DFTJonas Joos
CaZnOS:Mn2+ is a rare-earth-free luminescent compound with an orange broadband emission at 612 nm, featuring pressure sensing capabilities, often explained by defect levels where energy can be stored. Despite recent efforts from experimental and theoretical point of view, the underlying luminescence mechanisms in this phosphor still lack a profound understanding. By evaluation of the thermoluminescence as function of the charging wavelength, we probe the defect levels allowing the energy storage. Multiple trap depths and trapping routes are found, suggesting predominantly local trapping close to the Mn2+ impurity. We demonstrate that this phosphor shows mechanoluminescence which is unexpectedly stable at high temperature (up to 200°C), allowing pressure sensing in a wide temperature range. Next, we correlate the spectroscopic results with a theoretical study of the electronic structure and stability of the Mn defects in CaZnOS. DFT calculations at PBE+U level indicate that the Mn impurity is incorporated on the Zn site in a divalent charge state, which is confirmed by x-ray absorption spectroscopy (XAS). A ligand-to-metal charge transfer (LMCT) is predicted from the location of the Mn impurity levels, obtained from the calculated defect formation energies. This LMCT proves to be a very efficient pathway for the energy storage. The excited state landscape of the Mn2+ 3d5 electron configuration is assessed through the spin-correlated crystal field and a good correspondence with the emission and excitation spectra is found. In conclusion, studying phosphors at both a single-particle level (i.e. via calculation of defect formation energies) and a many-particle level (i.e. by accurately localizing the excited states) is necessary to obtain a complete picture of luminescent defects, as demonstrated in the case of CaZnOS:Mn2+.
Potentiostatic Deposition of ZnO Nanowires: Effect of Applied Potential and Z...IJRES Journal
In this work we report on potentiostatic deposition of Zinc oxide (ZnO) nanowires on fluorine-doped tin oxide (FTO) covered glass substrates from electroreduction of molecular oxygen. The influence of applied deposition potential, and the concentrations of zinc precursor (ZnCl2) on the properties of ZnO nanowires was investigated.SEM results revealed that ZnO nanowires electrodeposited at applied potential -0.85Vhave high density and good alignment. The diameters and densities of the electrodeposited ZnO nanowires are strongly dependent on the zinc ion concentrations and well aligned nanowires with uniform diameter can be obtained when the concentration of zinc ions is between 0.5 mM and 1 mM.
Introduction to nanoscience and nanotechnologyaimanmukhtar1
Introduction of nanoscience/nanotechnology ,properties/potential applications of nanomaterials and electrodeposition of metal single component and alloy nanowires in AAO template
Enzo palmieri experimental results on thermal boundary resistance for niobi...thinfilmsworkshop
Unless of a few eclectic scientists that have studied the problem of Kapitza resistance, a superconducting cavity is almost always seen as an adiabatic system of the electromagnetic fields interacting with a Niobium sheet cooled at 4,2K or at temperatures between 1,8K and 2 K. In this talk it will be shown that the real system to consider is that of Electromagnetic fields, Niobium and liquid Helium.
And liquid Helium is a component much more complex than an infinite heat exchanger at fixed temperature. Even at superfluid temperatures indeed, at the interface between Helium and the superfluid, it will be always a nanometric thick layer of normal helium and the thickness of this layer depends on the RF power.
Niobium sputtered cavities will be also examined under the point of view of thermal boundary Resistance, arriving to the conclusion that more advanced comprehension of SRF cannot prescind from a deep understanding of Cryogenics
Sarah aull secondary electron yield of srf materialsthinfilmsworkshop
In the quest of new materials for SRF applications, the secondary electron yield (SEY) needs also to be taken into consideration. A high SEY holds the risk that multipacting becomes again a main performance limitation of an SRF cavity. In the worst case, a too high SEY makes a material completely unsuitablefor an RF exposed surface. This talk will discuss general aspects of the role of the surface condition and present SEY measurements on different SRF relevant materials, i.e. MgB2, Nb3Sn and NbTiN.
Sarah aull secondary electron yield of srf materialsthinfilmsworkshop
In the quest of new materials for SRF applications, the secondary electron yield (SEY) needs also to be taken into consideration. A high SEY holds the risk that multipacting becomes again a main performance limitation of an SRF cavity. In the worst case, a too high SEY makes a material completely unsuitablefor an RF exposed surface. This talk will discuss general aspects of the role of the surface condition and present SEY measurements on different SRF relevant materials, i.e. MgB2, Nb3Sn and NbTiN.
Anne marie valente-feliciano - multilayer approach to increase the performanc...thinfilmsworkshop
For the past three decades, bulk niobium has been the material of choice for SRF cavities applications. RF cavity performance is now approaching the theoretical limit for bulk niobium. For further improvement of RF cavity performance for future accelerator projects, Superconductor-Insulator-Superconductor (SIS) multilayer structures (as proposed by Alex Gurevich) present the theoretical prospect to reach RF performance beyond bulk Nb, using thinly layered higher-Tc superconductors with enhanced Hc1. Jefferson Lab (JLab) is pursuing this approach with the development of NbTiN and AlN based multilayer SIS structures via magnetron sputtering and High Power Impulse Magnetron Sputtering (HiPIMS). This contribution presents the characterization of NbTiN and insulator films and some RF measurements on NbTiN-based multilayer structures.
Mahadevan krishnan coaxial energetic deposition of thin filmsthinfilmsworkshop
AASC has been studying thin film coating of Nb on coupon substrates as well as on1300MHz RF cells. At the last Thinfilm workshop in Padua, we reported on high RRR measurements and good crystallinity in Nb films coated onto crystal substrates such as a-sapphire, MgO and also on polished Copper coupons. Since then, we have coated several 1300MHz RF cells provided to us and tested by LANL, ANL and JLab. The Qo vs. E measurements suggest that better surface preparation is a must for high quality RF performance. Future work will coat Copper cells with different surface preparation (centrifugal barrel polishing and EP) and try to improve upon our preliminary results. Results from Nb films coated on to Al6061 coupons are encouraging and motivate coating of a barrel polished Aluminum RF cell. Recently AASC has embarked upon two new thinfilm coating projects: Nb on stainless steel bellows for SRF accelerators and Cu films on stainless steel tubes for high power RF Couplers. We are also collaborating with CERN to coat a Cu disk of a quadrupole resonator with Nb, for RF tests at high fields. This talk will provide details of all of these ongoing activities, all of which are supported by the US Department of Energy via SBIR contracts.
Surface Chemistry and Device Response of AlGaN/GaN SensorsJeremy Gillbanks
A copy of the presentation I delivered in September 2015 as part of my Final Year Project for the Master of Professional Engineering (Mechanical) at the University of Western Australia.
Please note: This was simply uploaded after the presentation was delivered as an example to friends studying engineering and what to expect in a final year presentation. Therefore, it lacks the full explanation required to understand the project in significant detail. Further information is available by contacting me directly.
This research furthered the development of micro-electro-mechanical sensors for use in recycled water monitoring and lab-on-a-chip medical devices. AlGaN/GaN sensors are superior to traditional ion-selective field effect transistor sensors because the are more stable, cost less and do not require a reference electrode.
Completing this project involved using the Australian Synchrotron to measure the molecular contact angle of three molecules, glycine, 6-amino-2-naphthoic acid in benzil, on the surface of an AlGaN/GaN high electron mobility transistor-based chemical sensor. The project was able to determine the angle for two out of the three chemicals used, which was a great success given the experimental difficulty of conducting near-edge x-ray absorption fine structure spectroscopy.
Krishnan - Energetic Condensation Growth of Nb films for SRF Acceleratorsthinfilmsworkshop
http://www.surfacetreatments.it/thinfilms
Energetic Condensation Growth of Nb films for SRF accelerators (Mahadevan Krishnan - 30')
Speaker: Mahadevan Krishnan - Alameda Applied Sciences Corporation | Duration: 30 min.
Abstract
AASC, Jefferson Lab and NSU conduct research into new SRF thin-film coatings by first characterizing the materials properties such as morphology, grain size, crystalline structure, defects, and impurities, then measuring properties such as Tc and RRR and following this with ‘in-cavity’ RF measurements of the Surface Impedance of the films at cryogenic temperatures. These progressive steps are essential to the eventual design of SRF accelerator structures and to measure Q-slope and other performance parameters at high fields.
This paper describes recent results from pure Nb thin-films grown on a-plane and c-plane sapphire, MgO as well as on amorphous substrates. Substrate preparation is shown to be critical to good electrical properties of the film. The sapphire and MgO substrates were heated up to 700 deg C and subsequently coated at 300, 500 and 700 deg C. Film thickness was varied from ~0.25µm up to >3µm. RRR and Tc were measured. The XRD data yielded pole figures, intensity vs. 2-θ and intensity vs. φ plots. These data were complemented by EBSD and SEM images. RRR values ranging from ~10 up to ~333 have been measured and correlated with the XRD data. Good crystallinity is associated with high RRR. Single crystalline (110) epitaxial layers of Nb films are grown well on a-plane sapphire substrates at different temperatures. Nb films have also been grown on Cu substrates, as well as on MgO and borosilicate substrates. The significance of crystalline structure observed on amorphous substrates is discussed in light of its implications for future, lower-cost SRF cavities.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
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We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
1. Innovative approach of Anode Functional Layer (AFL)
design for Solid Oxide Fuel Cell system
Da-hee Kang, Chan-ho Park, Hye-jin Jeon,
Hyeon-gwon Jeong, Jun-young Ko
EATED
Incheon national university
3. 1. Motivation
■ Anode Support SOFCs
▪ Application of Anode Functional Layer (AFL) to Solid Oxide Fuel Cell system is
always at the center of attention for their high performance and structural stability
▪ Ni-YSZ AFL has been widely used for conventional anode supported SOFC
▪ However, their severe operating temperature (up to 900℃) and redox cycle caused
agglomeration of Ni metal and delamination or mechanical failure of AFL layer
■ Ni nano-particle exsolved LCNT (La0.43Ca0.37Ni0.06Ti0.94O3-𝜹 ) Perovskite
▪ This nano structured AFL design prepared by exsolution method showed superior
stability such as resistance to catalyst agglomeration even under direct utilization of
hydrocarbon fuel
▪ The homogenously exsolved nano Ni particles on AFL backbone were successfully
maximized Three Phase Boundaries (TPBs), which is the critical requirement of SOFC
electrode design
4. 1. Motivation
▪ Perovskite based MIEC is considered the next generation
of SOFC anode materials because of their thermal, redox
stability and fuel flexibility
▪ Especially, in-situ nano-catalyst exsolution phenomenon
from the perovskite oxide phase showed high TPB density
and long term stability due to their socketed nano catalysts
that are dispersed on whole of the perovskite grain
▪ In our experiment, we synthesized LCNT perovskite phase
using solid state reaction method and confirmed exsolution
of Ni nanoparticles on the perovskite surface after
reduction
Exsolution conventional
▪ Also, the performance of LCNT unit cell was evaluated by comparing the I-V curves and EIS analysis
with the conventional Ni-YSZ AFL unit cell and the reference unit cell
■ Perovskite based mixed ionic and electronic conductor (MIEC)
6. 3.Result & Discussion
■ Exsolution of Ni Nano-particle – LCNT perovskite
▪ Before reduction, NiO-LCNT composite
showed NiO and LCNT peaks respectively
▪ It showed Ni and LCNT peaks without
secondary phase after reduction
▪ Stable synthesis of perovskite phase was
confirmed by XRD analysis
▪ SEM images show the surface and cross
section before and after reduction
▪ After the reduction, the exsolution of Ni
nano-particles on perovskite oxide surface
can be confirmed
(Dry H2 environment 900oC for 12h)
7. ■ Exsolution of Ni Nano-particle – LCNT perovskite
▪ FE-SEM images show microstructure of YSZ
electrolyte-AFL interface. Compared to Ni-YSZ,
the exsolution of Ni nano-particles that increase
TPBs were confirmed on LCNT perovskite oxide
surface in the vicinity of the YSZ electrolyte
▪ As a result of porosity analysis after reduction,
the porosity of Ni-YSZ AFL was 23.03%, while
the porosity of LCNT AFL was 13.81%
▪ Low porosity of LCNT inhibits gas transmission,
which reduces performance
▪ NiO-LCNT porosity increases as NiO is reduced
to Ni, so the amount of NiO can control the
porosity
▪ Electrodes, electrolytes, and AFL are all
controlled to be the same thickness for each cell
3.Result & Discussion
8. ■Performance at Diverse Temperature
3.Result & Discussion
▪ We conducted I-V curves and
EIS measurements at various
temperatures, and the
measurements at 900oC were
conducted 2 hours after the
reduction
▪ Result of I-V curves
measurements, maximum power
density of LCNT AFL unit cell
showed 0.9Wcm-2, whereas Ni-
YSZ AFL unit cell showed
1.6Wcm-2 at 900oC
▪ EIS analysis also showed that LCNT AFL have higher ohmic and polarization
resistance than Ni-YSZ AFL at all temperature
▪ The compact structure of the LCNT AFL (porosity 13.81%) increases resistance and
consequently
▪ Therefore, further studies on the composition of LCNT AFL should be conducted, and LCNT AFL unit
cells with optimized porosity and electrode microstructure will perform better than conventional
Ni-YSZ AFL unit cell under actual operating conditions
