To read this content please select one of the options below:

A micro room temperature oxygen sensor based on LaF3 solid electrolyte thin film

Yankun Tang (School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China and State Key Laboratory for Manufacturing System Engineering, Xi’an Jiaotong University, Xi’an, China)
Ming Zhang (School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China and State Key Laboratory for Manufacturing System Engineering, Xi’an Jiaotong University, Xi’an, China)
Kedong Chen (School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China and State Key Laboratory for Manufacturing System Engineering, Xi’an Jiaotong University, Xi’an, China)
Sher Ali Nawaz (School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China and State Key Laboratory for Manufacturing System Engineering, Xi’an Jiaotong University, Xi’an, China)
Hairong Wang (School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China and State Key Laboratory for Manufacturing System Engineering, Xi’an Jiaotong University, Xi’an, China)
Jiuhong Wang (School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an, China and State Key Laboratory for Manufacturing System Engineering, Xi’an Jiaotong University, Xi’an, China)
Xianqing Tian (Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, China)

Sensor Review

ISSN: 0260-2288

Article publication date: 24 August 2023

Issue publication date: 21 November 2023

147

Abstract

Purpose

Detecting O2 gas in a confined space at room temperature is particularly important to monitor the work process of precision equipment. This study aims to propose a miniaturized, low-cost, mass-scale produced O2 sensor operating around 30°C.

Design/methodology/approach

The O2 sensor based on lanthanum fluoride (LaF3) solid electrolyte thin film was developed using MEMS technology. The principle of the sensor was a galvanic cell H2O, O2, Pt | LaF3 | Sn, SnF2 |, in which the Sn film was prepared by magnetron sputtering, and the LaF3 film was prepared by thermal resistance evaporation.

Findings

Through pretreatments, the sensor’s response signal to 40% oxygen concentration was enhanced from 1.9 mV to 46.0 mV at 30°C and 97.0% RH. Tests at temperatures from 30°C to 50°C and humidity from 32.4% RH to 97.0% RH indicated that the output electromotive force (EMF) has a linear relationship with the logarithm of the oxygen concentration. The sensitivity of the sensor increases with an increase in both humidity and temperature in the couple mode, and the EMF of the sensor follows well with the Nernst equation at different temperatures and humidity.

Practical implications

This research could be applied to monitor the oxygen concentration below 25% in confined spaces at room temperature safely without a power supply.

Originality/value

The relationship between temperature and humidity coupling and the response of the sensor was obtained. The nano-film material was integrated with the MEMS process. It is expected to be practically applied in the future.

Keywords

Acknowledgements

This work is supported by National Key R&D Program of China (2022YFB3206800), NSAF (Grant No. U1930205), Science and Technology Planning Project of Shenzhen (Grant No. JSGG20191129102808151), Fundamental Research Funds for the Central Universities (Grant No. xzd012019020), Key Research and Development Projects of Shaanxi Province (Grant No. 2019GY-121, 2020GY-137). The authors appreciate the support from International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies.

Citation

Tang, Y., Zhang, M., Chen, K., Nawaz, S.A., Wang, H., Wang, J. and Tian, X. (2023), "A micro room temperature oxygen sensor based on LaF3 solid electrolyte thin film", Sensor Review, Vol. 43 No. 5/6, pp. 318-331. https://doi.org/10.1108/SR-02-2021-0044

Publisher

:

Emerald Publishing Limited

Copyright © 2023, Emerald Publishing Limited

Related articles