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

Abstract

Recent advance in two-dimensional (2D) materials is an essential factor to boosting modern electronics and optoelectronics. So far, transition metal dichalcogenides (TMDs) as an emerging member of 2D materials, the...

Ultrafast Polarization Sensitive Photodetector Based on MoS2/Ta2Pd3Se8 Hybrid Dimensional Heterostructure

“…When α = 0, the photocurrent is determined by the photogating effect involving the trapping state; when α = 1, the photocurrent is determined by the photoconductive effect. [ 32,33 ] The extracted α is between 0 and 1, indicating the coexistence of these two mechanisms in our MoS 2 /TPS photodiode with a positive bias applied. Furthermore, photoresponsivity ( R ), external quantum and efficiency (EQE) are important indicators of the device performance as defined by the following equations $$$$\begin{eqnarray}R = \frac{{{I}_{{\rm{ph}}}}}{{PS}}\ \end{eqnarray}$$$$ $$$$\begin{eqnarray}{\rm{EQE}} = R\frac{{hc}}{{e\lambda }}\ \end{eqnarray}$$$$where S is the effective area, e is the electron charge, h is Planck's constant, and c is the speed of light.…”

“…When 𝛼 = 0, the photocurrent is determined by the photogating effect involving the trapping state; when 𝛼 = 1, the photocurrent is determined by the photoconductive effect. [32,33] The extracted 𝛼 is between 0 and 1, indicating the coexistence of these two mechanisms in our MoS 2 /TPS photodiode with a positive bias applied. Furthermore, photoresponsivity (R), external quantum and efficiency (EQE) are important indicators of the device performance as defined by the following equations…”

“…Besides, the interface trapping effects are inevitable since both electrons and holes need to travel across the interface, which usually significantly slow down the response speed of the device. To address these issues, type-I band alignment heterostructure based on either p-p junction or n-n junction is proposed, so as to form unilateral depletion region at the interface, [31][32][33] where only one type of photogenerated carriers cross the heterointerface and rapidly recombine with the opposite carriers in the accumulation region (see more details in the Figure S1, Supporting Information). Thus, both the interlayer recombination of photogenerated electron-hole pairs and the interface trapping effects will be suppressed, resulting in improved device efficiency and response speed.…”

Interface engineering strategy for multisource spintronic devicesviaTMPS4modulation of black-phosphorus

“…26 Stacking this BP with TMPS 4 using the interfacial vdW force may further enrich the characteristics of both materials, especially promoting the application in spintronics and thermoelectric. [27][28][29] This is challenging because undesired band shifts will lead to photocarrier complexation and block photocarrier transport. 30,31 The layered dependence and diverse band structure of 2D materials make the structure a possible type II energy band alignment interface without electron and hole barriers, which is important for efficient charge transport and collection.…”

Broadband and High‐Performance Photodetector Fabricated Using Large Area and Transfer‐Free 2D–2D PtS2/MoS2 Heterostructure

“…In the past few years, most PtS 2 -based heterostructures have been fabricated using dry transfer of mechanically exfoliated flakes. [29][30][31] Although, this method is simple and quick but it possesses limitations for large-scale growth fabrication. So far, only Liang Li et al reported a combination of PtS 2 /MoS 2 heterostructures utilizing the same dry transfer approach, concentrating on visible range detection.…”