Fabrication and investigation of a new all-inorganic lead free perovskite Cs3Bi2I6 Br3 for ammonia detection at room temperature

Abstract A new all-inorganic lead free perovskite of Cs3Bi2I6Br3 has been synthesized by a simple liquid spin-coating method and applied for ammonia detection at room temperature. The successful formation was confirmed by XRD, FE-SEM, EDS and XPS. The sensing performance tests demonstrate that the responses of the device to ammonia are higher than those to ethanol and acetone. The top response value is of 11.8 to 500 ppm ammonia with satisfied recovery process, repeatability and improved stability of 14 days. Recoverable exchange between Cs+ ions located in octahedral vacancies and ammonia molecules should be in charge of the ammonia sensing mechanism. In contrast, electron transfer is responsible for the ethanol and acetone sensing processes. Our investigation offers a new strategy in the design of sensitive and potential green gas sensor in room temperature detection.