Study of Pre-Annealed ZnO-Added Lead-Free Perovskite-like material Cs3Bi2I9 for High Performance Ammonia Sensors

This study investigates the feasibility of using Cs 3 Bi 2 I 9 as a sensing material for ammonia (NH 3 ) and enhances its sensing performance by adding it with zinc oxide (ZnO) nanoparticles. After ZnO adding, the sensor’s responsivity to ammonia increases significantly, reaching 1044 -about 5.73 times higher than that of the unadded sample. This enhanced performance is primarily attributed to ZnO providing additional gas adsorption sites and facilitating more efficient charge carrier transport, thereby strengthening the sensor’s gas response capability. In addition, Cs 3 Bi 2 I 9 , as a lead-free perovskite, not only avoids the toxicity issues associated with conventional lead-based materials but also exhibits excellent humidity and long-term stability. Compared with organic–inorganic hybrid perovskites, the Cs 3 Bi 2 I 9 :pa-ZnO sensor shows superior stability and environmental adaptability. Overall, this study demonstrates the feasibility and potential of applying lead-free inorganic perovskites to gas sensing. • Cs 3 Bi 2 I 9 was used as a sensing material for ammonia (NH 3 ) and enhances its sensing performance by doping it with zinc oxide (ZnO) nanoparticles. • After ZnO doping, the sensor’s sensitivity to ammonia increases significantly, reaching 1044 -about 5.73 times higher than that of the undoped sample. • This enhanced performance is primarily attributed to ZnO providing additional gas adsorption sites and facilitating more efficient charge carrier transport, thereby strengthening the sensor’s gas response capability. • Compared with organic–inorganic hybrid perovskites, the pa-ZnO/Cs 3 Bi 2 I 9 sensor shows superior stability and environmental adaptability.