Two-dimensional Bi2O2Se nanosheets for sensitive and fast-response high-temperature photodetectors

Two-dimensional Bi2O2Se with unique crystal structure and ultrahigh carrier mobility has been catching widespread attention and demonstrated great potential in nanoelectronic and optoelectronic devices. The existence of lattice oxygen ensures its ultrahigh stability at ambient environment and make it promising for high-temperature applications. Here, through systematical characterizations, the high air stability of Bi2O2Se nanosheets at temperatures up to 250 °C is evidently demonstrated. The fabricated photodetectors based on the as-grown Bi2O2Se nanosheets show high stability, high sensitivity (∼5 319 A/W at 250 °C with a bias of 1 V) and fast response (several milliseconds) from room temperature to 250 °C. Besides, it was observed that the devices also show good photoresponse covering UV, visible and infrared regions at high temperatures. These results suggest their promising high-performance applications serving under harsh conditions.