Towards the optimization of a perovskite-based room temperature ozone sensor: A multifaceted approach in pursuit of sensitivity, stability, and understanding of mechanism

TL;DR

This study advances perovskite-based ozone sensors by exploring composition and doping effects, demonstrating improved sensitivity and stability through combined experimental and simulation approaches.

Contribution

It provides the first comprehensive evaluation of MHPs for ozone sensing, linking halide composition and Mn doping to sensor performance and stability.

Findings

Br-rich sensors show p-type response to O3

Mn-doping enhances gas adsorption and sensing performance

Long-term stability is affected by dynamic instabilities

Abstract

Metal halide perovskites (MHPs) have attracted significant attention owing to their simple manufacturing process and unique optoelectronic properties. Their reversible electrical or optical properties changes in response to oxidizing or reducing environments make them prospective materials for gas detection technologies. Despite advancements in perovskite-based sensor research, the mechanisms behind perovskite-gas interactions, vital for sensor performance, are still unexclusive. This work presents the first evaluation of the sensing performance and long-term stability of MHPs, considering factors such as halide composition variation and Mn doping levels. The research reveals a clear correlation between halide composition and sensing behavior, with Br-rich sensors displaying a p-type response to O3 gas, while Cl-based counterparts exhibit an n-type sensing behavior. Notably, Mn-doping significantly enhances the O3 sensing performance by facilitating the gas adsorption process, as supported by both atomistic simulations and experimental evidence. Long-term evaluation of the sensors provides valuable insights into evolving sensing behaviors, highlighting the impact of dynamic instabilities over time. Overall, this research offers insights into optimal halide combination and Mn-doping levels, representing a significant step forward in engineering room temperature perovskite-based gas sensors that are not only low-cost and high-performing but also durable, marking a new era in sensor technology.