Lan Zhaojue, Lei Yanlian, Chan Wing Kin Edward, Chen Shuming, Luo Dan, Zhu Furong
Department of Physics, Research Centre of Excellence for Organic Electronics, Institute of Advanced Materials, and State Key Laboratory of Environmental and Biological Analysis, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China.
Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Sci Adv. 2020 Jan 31;6(5):eaaw8065. doi: 10.1126/sciadv.aaw8065. eCollection 2020 Jan.
We report a dual-mode organic photodetector (OPD) that has a trilayer visible light absorber/optical spacer/near-infrared (NIR) light absorber configuration. In the presence of NIR light, photocurrent is produced in the NIR light-absorbing layer due to the trap-assisted charge injection at the organic/cathode interface at a reverse bias. In the presence of visible light, photocurrent is produced in the visible light-absorbing layer, enabled by the trap-assisted charge injection at the anode/organic interface at a forward bias. A high responsivity of >10 A/W is obtained in both short and long wavelengths. The dual-mode OPD exhibits an NIR light response operated at a reverse bias and a visible light response operated at a forward bias, with a high specific detectivity of ~10 Jones in both NIR and visible light ranges. A bias-switchable spectral response OPD offers an attractive option for applications in environmental pollution detection, bioimaging process, wellness, and security monitoring in two distinct bands.
我们报道了一种具有三层可见光吸收体/光学间隔层/近红外（NIR）光吸收体结构的双模式有机光电探测器（OPD）。在近红外光存在的情况下，由于在反向偏压下有机/阴极界面处的陷阱辅助电荷注入，在近红外光吸收层中产生光电流。在可见光存在的情况下，由于在正向偏压下阳极/有机界面处的陷阱辅助电荷注入，在可见光吸收层中产生光电流。在短波和长波中均获得了大于10 A/W的高响应度。该双模式OPD表现出在反向偏压下工作的近红外光响应和在正向偏压下工作的可见光响应，在近红外和可见光范围内均具有约10琼斯的高比探测率。一种偏置可切换光谱响应OPD为在两个不同波段的环境污染检测、生物成像过程、健康和安全监测等应用提供了一个有吸引力的选择。
