Dong Boheng, Zhang Xinya, Cheng Hui, Jiang Xiang, Wang Fuxian
School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology, Institute of Analysis, Guangdong Academy of Sciences (China National Analytical Center, Guangzhou), Guangzhou, Guangdong, 510070, China.
Nanoscale. 2023 Mar 30;15(13):6333-6342. doi: 10.1039/d3nr00118k.
CuBiO is a promising photoactive material for photoelectrochemical (PEC) broadband photodetectors due to its suitable band structure, but its photo-responsivity is severely limited by the short carrier diffusion length and long light penetration depth. To address the trade-off between light absorption and charge separation, a nano-structured bipolar BiO host scaffold was coupled with an ultrathin CuBiO light absorbing layer to construct a host-guest BiO/CuBiO photocathode. The work function of the bipolar BiO scaffold lies in between FTO and CuBiO, making BiO a suitable back contact layer for hole transport. Compared with the flat CuBiO and BiO scaffold counterpart, the nanostructured BiO/CuBiO exhibits significantly improved light absorption and enhanced charge separation efficiency. The BiO/CuBiO PEC photodetector can be self-powered and demonstrates a broad photo-response ranging from ultraviolet (UV) to near infrared (NIR). It shows a high responsivity of 75 mA W and a remarkable short response time of 0.18 ms/0.19 ms. BiO/CuBiO prepared by magnetron sputtering demonstrates great potential for rapid PEC photodetection in a wide optical domain.
由于其合适的能带结构，CuBiO是一种用于光电化学（PEC）宽带光电探测器的有前途的光活性材料，但其光响应性受到短载流子扩散长度和长光穿透深度的严重限制。为了解决光吸收和电荷分离之间的权衡问题，将纳米结构的双极BiO主体支架与超薄CuBiO光吸收层耦合，构建了一种主客体BiO/CuBiO光阴极。双极BiO支架的功函数介于FTO和CuBiO之间，使BiO成为用于空穴传输的合适背接触层。与平面CuBiO和BiO支架对应物相比，纳米结构的BiO/CuBiO表现出显著改善的光吸收和增强的电荷分离效率。BiO/CuBiO PEC光电探测器可以自供电，并展示出从紫外（UV）到近红外（NIR）的宽光响应。它显示出75 mA/W的高响应度和0.18 ms/0.19 ms的显著短响应时间。通过磁控溅射制备的BiO/CuBiO在宽光学域中展示了快速PEC光检测的巨大潜力。
