Colored Silicon Heterojunction Solar Cells Exceeding 23.5% Efficiency Enabled by Luminescent Down-Shift Quantum Dots
Conghui Jiang1, Guohua Zhang1, Zhiwei Hong1, Jiangyu Chen1, Ya Li2, Xianrong Yuan1, Yinyue Lin3, Cao Yu4, Tao Wang1, Tao Song1*, Yusheng Wang1,2*, and Baoquan Sun1,2*
1Jiangsu Key Laboratory of Advanced Negative Carbon Technologies,Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China.
2Macao Institute of Materials Science and Engineering (MIMSE) MUST-SUDA Joint Research Center for Advanced Functional Materials, Macau University of Science and Technology, Taipa, Macau 999078, China
3The Interdisciplinary Research Center, Shanghai Advanced Research Institute, Chinese Academy of Sciences 99 Haike Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai 201210, China
4Suzhou Maxwell Technologies Co. Ltd, Wujiang Economic Development Zone, Jiangsu, Suzhou 215200, China
Colored solar panels, realized by depositing various reflection layers or structures, are emerging as power sources for building with visual aesthetics. However, these panels suffer from reduced photocurrent generation due to the less efficient light harvesting from visible light reflection and degraded power conversion efficiency (PCE). Here, color-patterned silicon heterojunction solar cells are achieved by incorporating luminescent quantum dots (QDs) with high quantum yields as light converters to realize an asthenic appearance with high PCE. It is found that large bandgap (blue) QD layers can convert UV light into visible light, which can notably alleviate the parasitic absorption by the front indium tin oxide and doped amorphous silicon. Additionally, a universal optical path model is proposed to understand the light transmission process, which is suitable for luminescent down-shift devices. In this study, solar cells with a PCE exceeding 23.5% are achieved using the combination of a blue QD layer and a top low refractive index anti-reflection layer. Based on our best knowledge, the obtained PCE is the highest for a color-patterned solar cell. The results suggest an enhanced strategy involving incorporation of luminescent QDs with an optical path design for high-performance photovoltaic panels with visual aesthetics.