Multifunctional Photodetectors Based on Nanolayered Black Phosphorus/SnS0.5Se1.5 Heterostructures

Van der Waals (vdW) heterostructures have recently emerged as a promising artificial structure for nano-electronic and optoelectronic applications.In this work, we present electronic and phototransistor properties of BP/SnS0.5Se1.5 heterostructures.The backward diode behavior in the output characteristics reveal that the heterojunction is type-III broken-gap band alignment.Moreover, an unusual gate tuned plus-minus photoresponse characteristic is demonstrated.The positive photocurrent emerges at negative gate, while a negative photocurrent appears when a positive gate is applied.In addition, this effect can be tuned by the channel length of each material.Such devices demonstrate a promising potential in future electronic and optoelectronic applications.