Ultrasensitive, Superhigh Signal-to-Noise Ratio, Self-Powered Solar-Blind Photodetector Based on n-Ga2O3/p-CuSCN Core–Shell Microwire Heterojunction

• DOI: 10.1021/acsami.9b11012
• Publication Date: 2019-09-02T07:07:24Z
• Authors: Shan Li; Daoyou Guo; Peigang Li; Xia Wang; Yuehui Wang; Zuyong Yan; Zeng Liu; Yusong Zhi; Yuanqi Huang; Zhenping Wu; Weihua Tang
• Keywords: Photoelectric effect; Specific detectivity; Ultraviolet; Photodetection

Solar-blind photodetectors have captured intense attention due to their high significance in ultraviolet astronomy and biological detection. However, most of the solar-blind not shown extraordinary advantages weak light signal detection because forewarning low-dose deep-ultraviolet radiation is so important for human immune system. In this study, a high-performance photodetector constructed based on n-Ga2O3/p-CuSCN core-shell microwire heterojunction by simple immersion method. comparison with single device Ga2O3 CuSCN, demonstrates an enhanced photoelectric performance ultralow dark current 1.03 pA, photo-to-dark ratio 4.14 × 104, rejection (R254/R365) 1.15 104 under bias 5 V. Excitingly, heterostructure shows sensitivity (1.5 μW/cm2) deep high-resolution subtle change intensity (1.0 μW/cm2). Under illumination 254 nm at V, large responsivity 13.3 mA/W, superb detectivity 9.43 1011 Jones, fast response speed rise time 62 ms decay 35 ms. Additionally, can work without external power supply has specific spectrum selectivity as well excellent stability even through 1 month storage. Such prominent photodetection, profited novel geometric construction built-in electric field originating from p-n heterojunction, meets greatly "5S" requirements practical application.