Molecular Synergistic Effect for High Efficiency Monolithic Perovskite/Perovskite/Silicon Triple‐Junction Tandem Solar Cells

• Published in: Advanced energy materials 2024-11, Vol.14 (44), p.n/a
• Main Authors: Ye, Tianshi, Qiao, Liang, Wang, Tao, Wang, Pengshuai, Zhang, Lin, Sun, Ruitian, Kong, Weiyu, Xu, Menglei, Yan, Xunlei, Yang, Jie, Zhang, Xinyu, Ma, Linlin, Yang, Xudong
• Format: Article
• Language: English
• Subjects: Bonding strength; Chemical bonds; Dipole moments; Energy conversion efficiency; Energy levels; Functional groups; Hydrogen bonds; interface engineering; mixed‐halide wide‐bandgap perovskites; open‐circuit voltage deficit; perovskite/perovskite/silicon triple‐junction tandem solar cells; Perovskites; Photovoltaic cells; Radiative recombination; Silicon; Solar cells; Synergistic effect
• ISSN: 1614-6832; 1614-6840
• DOI: 10.1002/aenm.202402491

Perovskite/perovskite/silicon triple‐junction tandem solar cells (TSCs) hold promise for high power conversion efficiencies (PCE). However, the efficiency is still relatively low due to the non‐radiative recombination losses in wide‐bandgap top cells. These losses, attributed to the interface defect states and energy level mismatches, present considerable challenges to realizing high‐performance and stable TSCs. Here, the molecular synergistic effect (MSE) is exploited to passivate interface in 1.95 eV top cells. Piperazine‐1‐carboxamide hydrochloride (PCACl) is combined, which possesses strong dipole moments and passivating functional groups that can bind with two neighboring uncoordinated lead ions and form hydrogen bonds with halide atoms at perovskite surface, with 1,3‐propane‐diammonium iodide, which can reduce interface recombination through field‐effect passivation. The MSE enabled by PCACl and PDAI2 facilitates excellent energy level alignment and reduces non‐radiative recombination losses and light‐induced phase segregation. Finally, the target perovskite/perovskite/silicon triple‐junction TSC obtains an open‐circuit voltage of 3.07 V and a champion PCE of 25.2% (for a 1.035 cm2 aperture area). The molecular synergistic effect enabled by piperazine‐1‐carboxamide hydrochloride and 1,3‐propane‐diammonium iodide facilitates excellent energy level alignment and reduces non‐radiative recombination losses and light‐induced phase segregation. The target perovskite/perovskite/silicon triple‐junction tandem solar cell obtains an open‐circuit voltage of 3.07 V and a champion power conversion efficiency of 25.2% (for a 1.035 cm2 aperture area).