High-Performance p-BP/n-PdSe2 Near-Infrared Photodiode with Fast and Gate-Tunable Photoresponse

摘要： Van der Waals heterostructures composed of transition metal dichalcogenide (TMDs) materials have become a remarkable compact system that could offer an innovative architecture for advanced engineering in high-performance energy-harvesting and optoelectronic devices. Here, we report a novel van der Waals (vdW) TMDs heterojunction photo-diode composed of black phosphorus (p-BP) and palladium diselenide (n-PdSe2) which establish a high and tunable rectification and photoresponsivity. A high rectification up to ≈ 7.1 × 105 is achieved which is successfully tuned by employing the back gate voltage to the heterostructure devices. Besides, the device significantly shows the high and gate-controlled photoresponsivity of ?? = 9.6 × 105 ?? ?? ―1, 4.53 × 105 ???? ―1 and 1.63 × 105 ???? ―1 under the influence of light of different wavelengths (?? = 532, 1064 and 1310 nm) in visible and near-infrared regions respectively due to interlayer optical transition and low Schottky. The device also demonstrates extraordinary values of detectivity (?? = 5.8 × 1013 Jones) and external quantum efficiency (?????? ≈ 9.4 × 106), which are an order of magnitude higher than the currently reported values. The effective enhancement of photovoltaic characteristics in visible and infrared regions of this TMDs heterostructure based system has a huge potential in the field of optoelectronics to realize high-performance infrared photodetectors.