ppt for students

1. 1
 “ Study of ZnO nanoparticles for gas sensing applications and its
mathematical simulation.”
Presenting by
Sheetal Kumar Sahu
Raipur, Chhattisgarh
A Research Proposal
On

2. 2
Overview
 Background
 Objective
 Methodology
Synthesis of nanoparticles
Characterization of nanoparticles
Gas sensing characterization
 Expected outcomes
 Significance

3. 3
 Background
In recent years, application of nanoparticles within size range of 1–
100 nm has received significant attention due to their novel
properties and has come up as an area of extensive research.
Among various of nanoparticles, ZnO nanoparticles (n-ZnO) have
received more attention.
 ZnO is a wide-band-gap semiconductor (3.37 eV)
 High transmittance
 Good electrical conductivity.
 Excellent thermal, chemical and mechanical stability.
 Low cost, compatible to integrated Si chip technology
 High reactivity to hazardous gases
Source?
10 nm

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 Applications

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Objective
The objectives of this research proposal are :
 Synthesize and characterize ZnO nanoparticles (Hydrothermal method).
 Study its structural and optical properties ( XRD, SEM, TEM).
 The focus will be on developing a method for synthesizing ZnO nanoparticles using chemical methods, as well
as characterizing their properties such as size, shape, and surface charge.
 Gas sensing characterization.
 The gas sensing response, selectivity, sensitivity will be determined against various pollutants such as H2, NH3,
CO, HCHO, NO, NO2, C6H6, CH3COCH3, etc.
 Computational simulation to validate the adsorption-desorption mechanisms in ZnO when exposed to
gases using software like Siesta, DFT theory.

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Methodology

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Methodology
The synthesized nanoparticles will be characterized using various techniques such as
 TEM
 SEM
 XRD
 FTIR spectroscopy
 UV–Visible spectroscopy
These techniques provide the information on the formation, size, structure, and elemental composition of
nanoparticles

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Methodology
Gas sensing characterization:
 One of the most favorable environmental applications of nanotechnology has been in air pollution remediation in which
different nanomaterials are used as nanoadsorbents, nanocatalysts, nanofilters, and nanosensors.
 Nanomaterial enabled sensors are used for the detection of harmful gases such as hydrogen sulfide, sulphur dioxide, and
nitrogen dioxide.
 Semiconductor-based gas sensors are the important family of electronic devices that are widely used in various sciences
and industries.
 The basic principles of this type of sensor are based on the reaction of the gas molecules and the semiconductor surface.
 Therefore, nanostructured semiconductors are the best candidate for fabricating of this type of gas sensor due to their
high surface area/volume ratio.
 The gas sensing response, selectivity, sensitivity will be determined against various pollutants such as H2, NH3, CO, HCHO,
NO, NO2, C6H6, CH3COCH3, etc.

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Methodology
 Mathematical modeling/simulation:
 Adsorption energy calculation
 Charge transfer in the process of gas adsorption
 Interface model, reaction mechanism across the gas-sensing layer interface
 Band diagram of ZnO, density of states after gas adsorption
 Optical properties after gas adsorption
 Work function calculation
 Modelling of interface before and after gas exposure will be evaluated under the Density Functional
Theory (DFT) to understand the sensitivity and selectivity.

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Expected outcomes
The expected outcomes of this research proposal are:
 A robust gas sensor for detecting hazardous gas sensors
 Aim for high gas response and ultrasensitivity according different morphology of ZnO .
 Aim for low detection limit up to sub ppm level compared to existing reports.
 Mathematical models of optical, electric and gas sensing properties of ZnO to predict and
optimise sensitivity and selectivity parameters.
 Addition of other materials in conjunction with ZnO such as ZnO-graphene, ZnO-CNT and
ZnO-Mxene will be tried to improve the sensing efficiency in later stages of this work.

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Significance
This research proposal relevant to nanotechnology might explore the potential applications and implications of
nanomaterials in various fields including medicine, electronics, and energy.

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 Thanks