DOI: https://doi.org/10.29363/nanoge.hybridoe.2021.013
Publication date: 3rd December 2021
Compared with the single junction solar cell technology, perovskite/silicon tandem solar cells (PSTSCs) provide a foreseeable strategic opportunity to further increase the power conversion efficiency (PCE). Nowadays, a certified power conversion efficiency (PCE) of 29.8% for the monolithic PSTSCs has been obtained, which exceeds the single junction Shockley–Queisser limit (29.3%), indicating its tremendous potential in the photovoltaic energy field. Here, a n-i-p type PSTSCs was fabricated by solution two-step sequential deposition method. Lithium chloride (LiCl) was added into the tin oxide (SnO2) precursor solution, which simultaneously passivated the defects and increased the electron injection driving force at the electron transfer layer (ETL)/perovskite interface. Eventually, we achieved monolithic PSTSCs with an efficiency of 25.42% and VOC of 1.92 V, which is the highest PCE and VOC in N-I-P type perovskite/Si tandem devices . Moreover, we also deposited p-i-n type perovskite top cells on fully-textured c-Si solar cells to construct conformal-grown monolithic PSTSCs by evaporation-solution combination two-step method. A thermal-evaporated CsBr thin layer between the perovskite layer and the hole transport layer is introduced to construct a gradient perovskite absorber for optimized energy level alignment, so as to improve the VOC and fill factor (FF) of the device. Finally, the PSTSCs achieved an efficiency of 27.48% and was stable in nitrogen over 10,000 h.
The authors are grateful to acknowledge to the financial support of National Key Research and Development Program of China (Grant No. 2018YFB1500103), the National Natural Science Foundation of China (Grant No. 61674084), the Overseas Expertise Introduction Project for Discipline Innovation of Higher Education of China (Grant No. B16027), Tianjin Science and Technology Project (Grant No. 18ZXJMTG00220). Key R&D Program of Hebei Province (No. 19214301D), Natural Science Foundation of Tianjin (No. 20JCQNJC02070), China Postdoctoral Science Foundation (No. 2020T130317), and the Fundamental Research Funds for the Central Universities, Nankai University.