MoS2/SnO2 heterojunction-based self-powered photodetector

A heterostructure of MoS2/SnO2 has been fabricated. A SnO2 film was deposited by Sn sputtering followed by oxidation of a Sn film in the ambient. Later, a MoS2 film was deposited on SnO2 by pulsed laser deposition. The built-in electric potential generated at the SnO2/MoS2 interface facilitates self-powered broadband photodetection ranging from the ultraviolet-visible to near-infrared (NIR) wavelength. Under NIR illumination, the device exhibits excellent photoresponse with a responsivity of 0.35 A W−1 and a detectivity of 1.25 × 1011 Jones at 0 V. Moreover, the device shows faster response with rise/fall times as 153/200 ms. The excellent performance of the device is attributed to the high electron transport behavior of SnO2 and a built-in electric field at the interface.