2024 - Sustainable Industrial Processing Summit
SIPS 2024 Volume 7. Lipkowski Intl. Symp / Physical Chemistry
| Editors: | F. Kongoli, J. Atwood, L. Barbour, G. Duca, R. Kuroda, A. Legocki, M. Zaworotko |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2024 |
| Pages: | 171 pages |
| ISBN: | 978-1-998384-16-7 (CD) |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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ZnO BASED CO GAS SENSOR: A DFT STUDY
Gani Yergaliuly1; Abylay Tangirbergen2; Baktiyar Soltabayev1;1NAZARBAYEV UNIVERSITY, Astana, Kazakhstan; 2NAZARBAYEV UNIVERSITY, NATIONAL LABORATORY ASTANA, Astana, Kazakhstan;
Type of Paper: Regular
Id Paper: 442
Topic: 53
Abstract:
The detection of carbon monoxide (CO) gas is of significant importance in various industrial and environmental contexts due to its toxicity and prevalence. Zinc oxide (ZnO) has emerged as a promising material for gas sensing applications, particularly due to its unique electronic properties and surface reactivity. However, the performance of ZnO-based sensors is highly dependent on the nature of its surface, especially in the presence of defects, which can significantly alter the material's gas-sensing capabilities. This study employs Density Functional Theory (DFT) to systematically investigate the influence of various types of surface defects in ZnO on its interaction with CO molecules. By understanding the role of these defects, we aim to elucidate the mechanisms that govern the sensitivity and selectivity of ZnO-based sensors toward CO gas.
This study investigates the crystal lattice parameters and adsorption characteristics of carbon monoxide (CO) on a zinc oxide (ZnO) (100) surface using density functional theory (DFT) calculations. The ZnO (100) surface's structural parameters were evaluated, revealing lattice constants of a = 3.263 Å and c = 5.235 Å, with a volume of 48.30 ų, slightly deviating from Mohamed Achehboune et al. (2022) values. The adsorption energy for CO on the ZnO surface was -0.84 eV, indicating a favorable interaction [1]. The bond length between carbon (C) and zinc (Zn) increased from 2.02 Å to 2.1434 Å, while the bond length between oxygen (O) in CO and carbon decreased from 1.3 Å to 1.14 Å, with a bond order of one post-relaxation.
The study's findings align with experimental results by Quanzi Yuan et al. (2009), especially regarding bond length, angle adjustments, and the band gap energy increase upon CO adsorption [2]. The band gap modification was quantified using the sensitivity factor S = 10.18. This work provides critical insights into the adsorption mechanism of CO on ZnO surfaces, impacting the design and optimization of ZnO-based gas sensors. The analysis of adsorption energy, bond length alterations, and structural parameters offers a comprehensive understanding of interaction dynamics at the molecular level, crucial for advancing sensor technology in monitoring air quality and detecting hazardous gases.
This research has been funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP22785922).