Gas sensing mechanisms in ABO3 perovskite materials at room temperature: A review

This article is a summary of the latest literature on gas sensing properties of perovskite materials at room temperature. Among all types of sensors, the perovskite materials with a general stoichiometry of ABO3 have attracted extensive attention due to their ease of fabrication, high sensitivity, selectivity, and stability. However, high operating temperature is one of the limiting factors affecting the stability of the sensors. To resolve this challenge, several researchers have focused on developing perovskite gas sensors operating at room tempera-tures. In this review, room temperature perovskite gas sensors developed for detection of the various gases have been reviewed. Further, the sensing mechanism and the influential factors on the performance (sensitivity, selectivity, and stability) of the sensors have been discussed. In addition, the influence of the relative humidity, dopant, and morphology on the sensing mechanism and selectivity have been highlighted. It is concluded that dopants cause defects in ABO3 by creating oxygen vacancy and enhancing the gas sensing properties. Also, the uniform distribution of the pores on surface morphology boosts sensitivity. Understanding the operational mechanism is the heart of any sensor's development. This paper provides support for research on solving the problems related to perovskite gas sensing.