Broken-Gap PtS2/WSe2 van der Waals Heterojunction with Ultrahigh Reverse Rectification and Fast Photoresponse
| Autor: | Haifeng Du, Fakun Wang, Liang Li, Wensen Wei, Shiqi Yin, Chaoyang Tan, Kailang Liu, Tianyou Zhai, Jiawang Chen, Yuan Lu |
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| Rok vydání: | 2021 |
| Předmět: |
Photocurrent
Materials science business.industry General Engineering General Physics and Astronomy Photodetector Heterojunction 02 engineering and technology Photodetection 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Band offset 0104 chemical sciences symbols.namesake Rectification symbols Optoelectronics General Materials Science van der Waals force 0210 nano-technology business Quantum tunnelling |
| Zdroj: | ACS Nano. 15:8328-8337 |
| ISSN: | 1936-086X 1936-0851 |
| DOI: | 10.1021/acsnano.0c09593 |
| Popis: | Broken-gap van der Waals (vdW) heterojunctions based on 2D materials are promising structures to fabricate high-speed switching and low-power multifunctional devices thanks to its charge transport versus quantum tunneling mechanism. However, the tunneling current is usually generated under both positive and negative bias voltage, resulting in small rectification and photocurrent on/off ratio. In this paper, we report a broken-gap vdW heterojunction PtS2/WSe2 with a bilateral accumulation region design and a big band offset by utilizing thick PtS2 as an effective carrier-selective contact, which exhibits an ultrahigh reverser rectification ratio approaching 108 and on/off ratio over 108 at room temperature. We also find excellent photodetection properties in such a heterodiode with a large photocurrent on/off ratio over 105 due to its ultralow forward current and a comparable photodetectivity of 3.8 × 1010 Jones. In addition, the response time of such a photodetector reaches 8 μs owing to the photoinduced tunneling mechanism and reduced interface trapping effect. The proposed heterojunction not only demonstrates the high-performance broken-gap heterodiode but also provides in-depth understanding of the tunneling mechanism in the development of future electronic and optoelectronic applications. |
| Databáze: | OpenAIRE |
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