Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST) , Beijing 100083, China.
School of Material Science and Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
ACS Nano. 2017 Feb 28;11(2):1894-1900. doi: 10.1021/acsnano.6b07960. Epub 2017 Jan 18.
Although there are numerous approaches for fabricating solar cells, the silicon-based photovoltaics are still the most widely used in industry and around the world. A small increase in the efficiency of silicon-based solar cells has a huge economic impact and practical importance. We fabricate a silicon-based nanoheterostructure (p-Si/p-Si/n-Si (and n-Si)/n-ZnO nanowire (NW) array) photovoltaic device and demonstrate the enhanced device performance through significantly enhanced light absorption by NW array and effective charge carrier separation by the piezo-phototronic effect. The strain-induced piezoelectric polarization charges created at n-doped Si-ZnO interfaces can effectively modulate the corresponding band structure and electron gas trapped in the n-Si/n-ZnO NW nanoheterostructure and thus enhance the transport process of local charge carriers. The efficiency of the solar cell was improved from 8.97% to 9.51% by simply applying a static compress strain. This study indicates that the piezo-phototronic effect can enhance the performance of a large-scale silicon-based solar cell, with great potential for industrial applications.
虽然有许多制造太阳能电池的方法，但基于硅的光伏电池仍然是工业和全球应用最广泛的。硅基太阳能电池效率的微小提高将产生巨大的经济影响和实际重要性。我们制造了一种基于硅的纳米异质结构（p-Si/p-Si/n-Si（和 n-Si）/n-ZnO 纳米线（NW）阵列）光伏器件，并通过 NW 阵列显著增强光吸收和通过压光电效应有效分离电荷载流子来证明了器件性能的增强。在 n 掺杂 Si-ZnO 界面处产生的应变诱导压电极化电荷可以有效地调制相应的能带结构和电子气陷在 n-Si/n-ZnO NW 纳米异质结构中，从而增强局部电荷载流子的输运过程。通过简单施加静态压缩应变，太阳能电池的效率从 8.97%提高到 9.51%。这项研究表明，压光电效应可以提高大规模硅基太阳能电池的性能，具有巨大的工业应用潜力。
