High-Performance Photodetectors Based on MoTe₂–MoS₂ van der Waals Heterostructures

Abstract

Two-dimensional (2D) materials have got extensive attention for multifunctional device applications in advanced nanoelectronics and optoelectronics, such as field-effect transistors, photodiodes, and solar cells. In our work, we fabricated MoTe 2 –MoS 2 van der Waals heterostructure photodetectors with great performance using the mechanical exfoliation method and restack technique. It is demonstrated that our MoTe 2 –MoS 2 heterostructure photodetector device can operate without bias voltage, possessing a low dark current (10 pA) and high photocurrent on/off ratio (>10 4 ). Importantly, the room temperature photoresponsivity of the MoTe 2 –MoS 2 photodetector can reach 110.6 and 9.2 mA W –1 under λ = 532 and 1064 nm incident laser powers, respectively. Our results indicate that the van der Waals heterostructure based on 2D semiconducting materials is expected to play an important role in nanoscale optoelectronic applications.

High-Gain MoS2/Ta2NiSe5 Heterojunction Photodetectors with Charge Transfer and Suppressing Dark Current

“…An extremely high responsivity of 515.6 A W –1 is obtained at the incident power density of 17.5 mW cm –2 , which is higher than that of all Ta 2 NiSe 5 -based phototransistors. − ,, Because of the low dark current of the heterojunction device (Figure S6a), the D * of the MoS 2 /Ta 2 NiSe 5 photodetector is up to the highest value of 3.1 × 10 13 Jones, which is comparable to that of the pure MoS 2 (∼3.9 × 10 12 Jones) and Ta 2 NiSe 5 devices (∼1.2 × 10 12 Jones). The D * of the heterostructure is superior to that reported in the MoS 2 /PdSe 2 photodetector (6.3 × 10 10 Jones), MoS 2 /MoTe 2 photodetector (1.4 × 10 8 Jones), and MoS 2 /GaSe photodetector (2.3 × 10 11 Jones) …”

“…[15][16][17]46,47 Because of the low dark current of the heterojunction device (Figure S6a), the D* of the MoS 2 / Ta 2 NiSe 5 photodetector is up to the highest value of 3.1 × 10 13 Jones, which is comparable to that of the pure MoS 2 (∼3.9 × 10 12 Jones) and Ta 2 NiSe 5 devices (∼1.2 × 10 12 Jones). The D* of the heterostructure is superior to that reported in the MoS 2 /PdSe 2 photodetector (6.3 × 10 10 Jones), 49 MoS 2 / MoTe 2 photodetector (1.4 × 10 8 Jones), 48 and MoS 2 /GaSe photodetector (2.3 × 10 11 Jones). 50 As described in Figure 5c, the EQE displays a similar trend with the power density compared with R and D*.…”

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

“…As compared with the traditional heterostructures, vdWHs possess the advantages of no dangling bonds and lattice mismatch, which provides opportunities to fabricate vdWHs with unique properties by infinitely combining different 2D materials. [9][10][11][12][13][14] Thus far, many kinds of vdWHs such as BP/ MoS 2 , [15][16][17] InSe/Se, 18 InSe/Te, 19 MoTe 2 /MoS 2 , 1,14,20,21 InSe/BP 22 and MoS 2 /WS 2 23 have been demonstrated and have shown a preferable photoresponse. However, the EQE and responsivity of these heterojunction photodetectors are still low and most of these heterojunctions are constructed by films with a thickness of several nanometers forming an ultrathin bilateral depletion region (or bilateral accumulation region).…”

2D MoTe2/MoS2−xOx Van der Waals Heterostructure for Bimodal Neuromorphic Optoelectronic Computing

“…As a result, a constant current is achieved in the forward direction. [45][46][47][48][49] Conversely, when the laser stimulus is irradiated in the negative electrode region, the photogenerated electrons from the MoS 2−x O x interface layer become trapped in the MoTe 2 and MoS 2−x O x stacking region. This causes a decrease in the number of transferred free electrons and a continuous decrease in the negative photocurrent.…”