Photoresponse of wafer-scale palladium diselenide films prepared by selenization method

Palladium diselenide (PdSe2) films exhibit a high charge carrier mobility and sensitivity in photodetection. In this work, wafer-scale PdSe2 thin films with controllable thickness have been synthesized by the selenization of Pd films. A PdSe2-based photodetector can detect a broad wavelength ranging from 420 nm to 1200 nm. The responsivity and detectivity can reach 1.96 × 103 A W−1 and 1.72 × 1010 W Hz−1/2 at VSD = 3 V, respectively. The figure of merit of the photodetection are comparable to the mechanically exfoliated PdSe2 based photodetector. This work demonstrated that selenization is a facile method to synthesize PdSe2 films in large scale and the films are promising for broadband photodetection.