Enhancing the photoresponse of single-layered semiconductor materials is a challenge for high-performance photodetectors due to atomically thickness and limited quantum efficiency of these devices. Band engineering in heterostructure of transition metal chalcogenides (TMDs) can sort out part of this challenge. Here, we address this issue by utilizing the plasmonics phenomenon to enrich the optoelectronics property of the WSe2/MoS2 heterojunction and further enhancement of photoresponse. The introduced approach presents a contamination-free, tunable and efficient way to improve light interactions with heterojunction devices. The results showed a 3600-fold enhancement in photoresponsivity and a 46-fold increase in external quantum efficiency (549%) along with a fast photoresponse time (~2 μs) and light polarization dependence. This improvement may assign to multiple light scatterings by the Au nanoarrays and creation of strong local electrical fields (hot spots) at the interfaces of the gold nanoarrays and the TMDs heterostructure. The high-energy electrons (hot electrons) originating from hot spots surmount easily to conduction bands of heterojunction which is leading to a remarkable enhancement of photocurrent. The plasmons assisted photoresponse strategy can be easily matched with the semiconductor industry to boost the performance of optoelectronics devices for practical applications.

Self-powered detectors based on triboelectric nanogenerators (TENG) have been considered because of their capability to convert ambient mechanical energy to electrical out-put signal, instead of conventional usage of electrochemical batteries as power sources. In this regard, the self-powered photodetectors have been designed through totally two lay out called passive and active circuit. in former model, impedance matching between the TENG and the resistance of the circuit’s elements is crucial, which is not investigated systematically till now. In this paper, a cost effective novel planar photodetector (PD) based on heterojunction of SnS2 sheets and Cs0.05(FA0.83 MA0.17)0.95Pb(I0.83Br0.17)3 three cationic lead iodide based perovskite (PVK) layer fabricated which powered by graphene oxide (GO) paper and Kapton based contact-separated TENG (CS-TENG). To achieve the high performance of this device, the proper range of the load resistances in the circuit regards to TENG’s characterization has been studied. In the next steps, the integrated self-powered photo-detection system was designed by applying Kapton/FTO and hand/FTO TENG, separately, in the proposed impedance matching circuit. The calculated D* of integrated self-powered SnS2/PVK supplied by tapping the Kapton and hand on FTO is 2.83 × 1010 and 1.10 × 1013 Jones under the 10 mW/cm2 of white light intensity, the investigations determine that for designing significate performance of self-powered PD supplied by TENG, the existence of the load resistance with the well match amount to the utilized TENG is crucial. Our results which can be generalized to other types of passive self-powered sensors, are substantial to both academia and industry concepts.

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High-performance photodetectors play critical roles in numerous photon-based applications in imaging, communication, and energy harvesting. Nowadays, heterostructures have received significant attention to extend the performance of photodetectors, with exceptionally high optical absorption and a wide absorption range. However, the enhancement factors, exact mechanism, and facile fabrication procedures are long-standing problems. Here, a heterojunction of a two-dimensional chemical vapor deposition-grown monolayer of WSe 2 with a Cu 2 ZnSnS 4 (CZTS) film is introduced. The CZTS film as an abundant material was synthesized in the form of nanoparticles, and it showed a great effect on the enhancement of light absorption. By control of the gate voltage, the results of optoelectronic measurements reveal fast response (2.5 ms) and broadband photoresponsivity (∼550 A/W for 395−980 nm), which are about 2500 times higher than those of a conventional WSe 2 structure. The energy band structure at the interface of the heterojunction and simulated data with/without a gate voltage were used to investigate the device operation mechanism. It has been realized that the gate voltage has direct impacts on increasing the photocurrent and suppressing the recombination of the photocarriers. The observed experimental results and the proposed mechanism pave shortcuts to developing efficient photodetectors based on transition metal dichalcogenides and earth-abundant materials.

High-performance photodetectors play crucial roles as an essential tool in many fields of science and technology, such as photonics, imaging, spectroscopy, and data communications. Demands for desired efficiency and low-cost new photodetectors through facile manufacturing methods have become a long-standing challenge. We used a simple successive ionic layer adsorption and reaction (SILAR) method to synthesize CdS, CdSe, and PbS nanoparticles directly grown on WSe2 crystalline flakes. In addition to the excellent wavelength selectivity for (30 nm) CdS, (30 nm) CdSe, and (6 nm) PbS/WSe2 heterostructures, the hybrid devices presented an efficient photodetector with a photoresponsivity of 48.72 A/W, a quantum efficiency of 71%, and a response time of 2.5–3.5 ms. Considering the energy band bending structure and numerical simulation data, the electric field distribution at interfaces and photocarrier generation/recombination rates have been studied. The introduced fabrication strategy is fully compatible with the semiconductor industry process, and it can be used as a novel method for fabricating wavelength-tunable and high-performance photodetectors toward innovative optoelectronic applications.