Efficiency improvement of silicon solar cells enabled by ZnO nanowhisker array coating
State Key Laboratory of Silicon Materials, Department of Materials Science & Engineering, Zhejiang University, Hangzhou, Zhejiang Province, 310027, Peoples Republic of China
Nanoscale Research Letters 2012, 7:306 doi:10.1186/1556-276X-7-306Published: 15 June 2012
An efficient antireflection coating is critical for the improvement of silicon solar cell performance via increased light coupling. Here, we have grown well-aligned ZnO nanowhisker (NW) arrays on Czochralski silicon solar cells by a seeding-growth two-step process. It is found that the ZnO NWs have a great effect on the macroscopic antireflection effect and, therefore, improves the solar cell performance. The ZnO NW array-coated solar cells display a broadband reflection suppression from 500 to 1,100 nm, and the minimum reflectance smaller than 3% can easily be achieved. By optimizing the time of ZnO NW growth, it has been confirmed that an increase of 3% relatively in the solar cell efficiency can be obtained. These results are quite interesting for the application of ZnO nanostructure in the fabrication of high-efficiency silicon solar cells.