Purpose

This paper aims to estimate the relationship between defect structure with gas concentration for use as a gas sensor. The change in defect concentration caused a shift in the Fermi level, which in turn changed the surface potential, which is manifested as the potentiometric response of the sensing element.

Design/methodology/approach

A new theoretical concept based on defect chemistry and band structure was used to explain the experimental gas response of a sensor. The theoretically simulated response was compared with experimental results.

Findings

Understanding the origin of potentiometric response, through the generation of defects and a corresponding shift in Fermi level of sensing surface, by the adsorption of gas. Through this understanding, the design of a sensor with improved selectivity and stability to a gas can be achieved by the study of defect structure and subsequent band analysis.

Research limitations/implications

This paper provides information about various types of surface defects and numerical simulation of material with defect structure. The Fermi energy of the simulated value is correlated with the potentiometric sensor response.

Practical implications

Gas sensors are an integral part of vehicular and industrial pollution control. The theory developed shows the origin of response which can help in identifying the best sensing material and its optimum temperature of operation.

Social implications

Low-cost, reliable and highly sensitive gas sensors are highly demanded which is fulfilled by potentiometric sensors.

Originality/value

The operating principle of potentiometric sensors is analyzed through electron band structure analysis. With the change in measured gas concentration, the oxygen partial pressure changes. This results in a change in defect concentration in the sensing surface. Band structure analysis shows that change in defect concentration is associated with a shift in Fermi level. This is the origin of the potentiometric response.

中文翻译：

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缺陷在La2CuO4电子能带结构和气体传感器响应中的作用

目的

本文旨在评估用作气体传感器的缺陷结构与气体浓度之间的关系。缺陷浓度的变化引起费米能级的变化，从而改变了表面电势，这表现为传感元件的电位响应。

设计/方法/方法

基于缺陷化学和能带结构的新理论概念被用来解释传感器的实验气体响应。将理论上模拟的响应与实验结果进行了比较。

发现

通过缺陷的产生以及感应表面费米能级的相应偏移（通过气体的吸附）来了解电位响应的起源。通过这种理解，可以通过研究缺陷结构和随后的谱带分析来实现对气体具有更高的选择性和稳定性的传感器设计。

研究局限/意义

本文提供了有关各种类型表面缺陷的信息以及具有缺陷结构的材料的数值模拟。模拟值的费米能量与电位传感器的响应相关。

实际影响

气体传感器是车辆和工业污染控制的组成部分。提出的理论表明了响应的起源，可以帮助确定最佳的传感材料及其最佳工作温度。

社会影响

电位计传感器满足了对低成本，可靠和高度灵敏的气体传感器的需求。

创意/价值

通过电子能带结构分析来分析电位传感器的工作原理。随着测量气体浓度的变化，氧分压也会变化。这导致感测表面中的缺陷浓度变化。能带结构分析表明，缺陷浓度的变化与费米能级的变化有关。这是电位响应的起源。