Ultrasensitive and Broad‐Spectrum Photodetectors Based on InSe/ReS₂ Heterostructure

Abstract

based on a sole 2D material to have the above two capabilities at the same time. Thus, a crucial issue for the next-generation 2D-material-based photodetectors is to explore a suitable strategy to achieve both high sensitivity and broad-spectrum response.Van der Waals (vdW) heterostructure created by stacking different 2D materials with highly distinct electronic states have shown interesting electronic and optical properties. [7,8] Nowadays, employing vdW heterostructure based on photogating effect demonstrates significant promise for revealing many intriguing physical phenomena and designing optoelectronic devices with superior performance. [8][9][10][11][12][13][14] Rhenium disulfide (ReS 2 ), as a member of the TMDs, has been widely researched due to its high light absorption capability, structural flexibility, and direct bandgap independent of thickness. [15] The photodetectors prepared by a few layers of ReS 2 have shown an ultrahigh responsivity of 88 600 A W −1 , indicating that ReS 2 could serve as a prospective material for future optoelectronic applications. [16] Indium selenide (InSe) has recently been found to display a wide bandgap window ranging from ≈1.25 eV in bulk to ≈2.2 eV in the monolayer. [17][18][19] High carrier mobility (≈10 3 cm 2 V −1 s −1 ) allows for extremely fast response of photodetectors based on InSe and its heterojunctions. [18,20] Thus, it is possible to enhance the overall performance of the photodetector by combining the advantages of InSe and ReS 2 .In this work, a high-performance photodetector based on InSe/ReS 2 vertical heterojunction is fabricated, in which ReS 2 acts as the transport layer, and the top layer InSe serves as the photogate to regulate the channel current. Benefiting from the vertical structure and excellent interface quality, the photodetector demonstrates excellent photodetection ability. On the one hand, the detectivity of the photodetector shows an ultrahigh value of over 10 13 Jones and even over 10 14 Jones at higher drain voltage, which is much higher than other reported photodetectors based on 2D materials. [10,[20][21][22][23][24][25] The photodetector exhibits a high responsivity of 1921 A W −1 , an ultrahigh external quantum efficiency (EQE) of 6.53 × 10 5 %, and a fast response time of 21.6 ms. On the other hand, the photoresponse of photodetectors ranges from the ultraviolet (365 nm) to the near-infrared (965 nm). The ultrahigh sensitivity, broad-spectrum response, and high-efficiency of the photodetector suggest that the InSe/ ReS 2 vertical heterostructure is promising for fast and ultrasensitive broad-spectrum photodetectors. Photogating effect based on vertical structure of 2D materials allows for the realization of a highly sensitive photodetector. A highly sensitive and broadspectrum (365-965 nm) photodetector is reported based on the indium selenide (InSe)/rhenium disulfide (ReS 2 ) vertical heterostructure, where the top layer InSe serves as the photogate to regulate the channel current, enabling a large photoconductive gain of 10 6 . ...

Type-I PtS2/MoS2 van der Waals heterojunctions with tunable photovoltaic effects and high photosensitivity

“…However, it is difficult for most photodetectors based on a single 2D material to cover all the requirements in complex practical application processes at the same time, for instance, fast response speed, excellent responsivity or high external quantum efficiency (EQE). 1,7,8 Therefore, combining the unique properties of different 2D materials maybe an alternative way to deal with such problems. Benefiting greatly from the weak van der Waals force between layers, different 2D materials could be stacked vertically to compose artificial heterostructures commonly known as van der Waals heterostructures (vdWHs).…”

A high-performance self-powered photodetector based on WSe2–graphene–MoTe2 van der Waals heterojunctions

“…8 Through flexible hetero-integration, TMDs are stacked into a rich variety of van der Waals heterojunctions (vdWHs) for diverse and outstanding optoelectronic properties. [9][10][11][12][13][14][15] Photodetectors are one of the key components of multifunctional technology and many devices. [16][17][18] TMDs have strong light-matter interactions and ultra-wide band gaps from visible to infrared.…”

“…8 Through flexible hetero-integration, TMDs are stacked into a rich variety of van der Waals heterojunctions (vdWHs) for diverse and outstanding optoelectronic properties. 9–15…”

Bias-Modified Schottky Barrier Height-Dependent Graphene/ReSe2 van der Waals Heterostructures for Excellent Photodetector and NO2 Gas Sensing Applications

“…Furthermore, heterostructures (HS) fabricated on either TMDs or with other low-dimensional electronic materials have been found to demonstrate outstanding optoelectronic and gas sensing performance in comparison to their counterparts [ 24 , 25 , 26 ]. For instance, PbS quantum dots (PbS-QDs)/MoS 2 heterostructure have shown a tremendously high photoresponsivity (~6 × 10 5 AW −1 ) as compared to only an MoS 2 photodetector.…”