Highly Sensitive H<sub>2</sub>S Gas Sensor Based on a Lead-Free CsCu<sub>2</sub>I<sub>3</sub> Perovskite Film at Room Temperature
Kai Ou, Yue Wang, Wenting Zhang, Yongliang Tang, Yuxiang Ni, Yudong Xia, Hongyan Wang
Abstract
High Resolution Image Download MS PowerPoint Slide Recently, there have been reports of lead halide perovskite-based sensors demonstrating their potential for gas sensing applications. However, the toxicity of lead and the instability of lead-based perovskites have limited their applications. This study addressed this issue by developing a H 2 S gas sensor based on a lead-free CsCu 2 I 3 film prepared using a one-step CVD method. The sensor demonstrated excellent sensing properties, including a high response and selectivity toward H 2 S, even at low concentrations (0.2 ppm) at room temperature. Furthermore, a reasonable sensing mechanism was proposed. It is suggested that the sensing mechanism sheds light on the role of defects in perovskite materials, the impact of H 2 S as an electron donor, and the occurrence of reversible chemical reactions. These findings suggest that lead-free CsCu 2 I 3 has great potential in the field of H 2 S gas sensing.