Han Taotao, Luo Mingwei, Liu Yuqi, Lu Chunhui, Ge Yanqing, Xue Xinyi, Dong Wen, Huang Yuanyuan, Zhou Yixuan, Xu Xinlong
Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710069, China.
Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710069, China.
J Colloid Interface Sci. 2022 Dec 15;628(Pt B):886-895. doi: 10.1016/j.jcis.2022.08.072. Epub 2022 Aug 17.
Photoelectrochemical (PEC)-type devices provide promising ways for harvesting solar energy and converting it to electric and chemical energy with a low-cost and simple manufacturing process. However, the high light absorption, fast carrier separation, and low carrier recombination are still great challenges in reaching high performance for PEC devices. As emergent two-dimensional (2D) materials, SbSe and SbS exhibit desirable photoelectric properties due to the narrow bandgap, large optical absorption, and high carrier mobility. Herein, SbS/SbSe heterojunction is synthesized by a two-step physical vapor deposition method. The type-II SbS/SbSe heterojunction displays excellentphotoelectric properties such as a high photocurrent density (I ∼ 162 µA cm), a high photoresponsivity (R ∼ 3700 µA W), and a fast time response speed (rising time ∼ 2 ms and falling time ∼ 4.5 ms) even in harsh environment (HSO electrolyte). Especially, the SbS/SbSe shows an excellent self-powered photoresponse (I ∼ 40 µA cm, R ∼ 850 µA W). This increment is attributed to the improvement in light absorption, charge separation, and charge transfer efficiency. Taking these advantages, the SbS/SbSe heterojunction also exhibits higher PEC water splitting synergically, which is approximately 3 times larger than that of SbSe and SbS. These results pave the way for high-performance PEC devices by integrating 2D narrow bandgap semiconductors.
光电化学（PEC）型器件为收集太阳能并将其以低成本和简单制造工艺转化为电能和化学能提供了有前景的途径。然而，高光吸收、快速载流子分离和低载流子复合在实现PEC器件的高性能方面仍然是巨大挑战。作为新兴的二维（2D）材料，SbSe和SbS由于其窄带隙、大光吸收和高载流子迁移率而展现出理想的光电特性。在此，通过两步物理气相沉积法合成了SbS/SbSe异质结。II型SbS/SbSe异质结显示出优异的光电特性，如高光电流密度（I ∼ 162 μA cm）、高光电响应度（R ∼ 3700 μA W）以及即使在恶劣环境（HSO电解液）下也具有快速的时间响应速度（上升时间 ∼ 2 ms，下降时间 ∼ 4.5 ms）。特别地，SbS/SbSe展现出优异的自供电光响应（I ∼ 40 μA cm，R ∼ 850 μA W）。这种提升归因于光吸收、电荷分离和电荷转移效率的提高。凭借这些优势，SbS/SbSe异质结协同展现出更高的PEC水分解效率，比SbSe和SbS的效率大约高3倍。这些结果为通过集成二维窄带隙半导体实现高性能PEC器件铺平了道路。
