Efficient and stable perovskite-silicon tandem solar cells through contact displacement by MgF x

• DOI: 10.1126/science.abn8910
• Publication Date: 2022-06-23T17:59:10Z
• Authors: Jiang Liu; Michele De Bastiani; Erkan Aydin; George T. Harrison; Yajun Gao; Rakesh R. Pradhan; Mathan K. Eswaran; Mukunda Mandal; Wenbo Yan; Akmaral Seitkhan; Maxime Babics; Anand S. Subbiah; Esma Ugur; Fuzong Xu; Lujia Xu; Mingcong Wang; Atteq ur Rehman; Arsalan Razzaq; Jingxuan Kang; Randi Azmi; Ahmed Ali Said; Furkan H. Isikgor; Thomas G. Allen; Denis Andrienko; Udo Schwingenschlögl; Frédéric Laquai; Stefaan De Wolf
• Keywords: 621; 530; 01 natural sciences; 7. Clean energy; 0104 chemical sciences

The performance of perovskite solar cells with inverted polarity (p-i-n) is still limited by recombination at their electron extraction interface, which also lowers the power conversion efficiency (PCE) of p-i-n perovskite-silicon tandem solar cells. A MgF

x

interlayer with thickness of ~1 nanometer at the perovskite/C 60 interface favorably adjusts the surface energy of the perovskite layer through thermal evaporation, which facilitates efficient electron extraction and displaces C 60 from the perovskite surface to mitigate nonradiative recombination. These effects enable a champion open-circuit voltage of 1.92 volts, an improved fill factor of 80.7%, and an independently certified stabilized PCE of 29.3% for a monolithic perovskite-silicon tandem solar cell ~1 square centimeter in area. The tandem retained ~95% of its initial performance after damp-heat testing (85°C at 85% relative humidity) for >1000 hours.