Highly Efficient Van Der Waals Heterojunction on Graphdiyne toward the High‐Performance Photodetector
Dinh Phuc, Chengyun Hong, Viet Q. Bui, Thi Hue Pham, Sohyeon Seo, Van Dam, Thanh Luan Phan, Kim My Tran, Surajit Haldar, Byungwook Ahn, Seong Chu Lim, Woo Jong Yu, Seong‐Gon Kim, Ji‐Hee Kim, Hyoyoung Lee
Abstract
Abstract Graphdiyne (GDY), a new 2D material, has recently proven excellent performance in photodetector applications due to its direct bandgap and high mobility. Different from the zero‐gap of graphene, these preeminent properties made GDY emerge as a rising star for solving the bottleneck of graphene‐based inefficient heterojunction. Herein, a highly effective graphdiyne/molybdenum (GDY/MoS 2 ) type‐II heterojunction in a charge separation is reported toward a high‐performance photodetector. Characterized by robust electron repulsion of alkyne‐rich skeleton, the GDY based junction facilitates the effective electron–hole pairs separation and transfer. This results in significant suppression of Auger recombination up to six times at the GDY/MoS 2 interface compared with the pristine materials owing to an ultrafast hot hole transfer from MoS 2 to GDY. GDY/MoS 2 device demonstrates notable photovoltaic behavior with a short‐circuit current of −1.3 × 10 −5 A and a large open‐circuit voltage of 0.23 V under visible irradiation. As a positive‐charge‐attracting magnet, under illumination, alkyne‐rich framework induces positive photogating effect on the neighboring MoS 2 , further enhancing photocurrent. Consequently, the device exhibits broadband detection (453–1064 nm) with a maximum responsivity of 78.5 A W −1 and a high speed of 50 µs. Results open up a new promising strategy using GDY toward effective junction for future optoelectronic applications.