Interfacial Engineering of Wide-Bandgap Perovskites for Efficient Perovskite/CZTSSe Tandem Solar Cells

作者：Wang, Deng; Guo, Hongling; Wu, Xin; Deng, Xiang; Li, Fengzhu; Li, Zhen; Lin, Francis; Zhu, Zonglong; Zhang, Yi^*; Xu, Baomin^*; Jen, Alex K. Y.^*

来源：Advanced Functional Materials, 2022, 32(2): 2107359.

DOI：10.1002/adfm.202107359

• interfacial engineering
• non-radiative recombination
• quasi-2D perovskite interfaces
• V
• (OC) deficit
• wide-bandgap perovskite solar cells

Wide-bandgap perovskites have attracted substantial attention due to their important role in serving as a top absorber in tandem solar cells (TSCs). However, wide-bandgap perovskite solar cells (PVSCs) typically suffer from severe non-radiative recombination loss and therefore exhibit high open-circuit voltage (V-OC) deficits. To address these issues, a 2D octyl-diammonium lead iodide interlayer is adopted onto the hole-transporting layer to induce the formation of an ultrathin quasi-2D perovskite that is close to the hole-selective interface. This approach not only accelerates hole transfer and retards hole accumulation but also reduces the trap density in the perovskite layer on top, thereby efficiently suppresses non-radiative recombination pathways. Consequently, the champion wide-bandgap device (approximate to 1.66 eV) exhibits a power conversion efficiency (PCE) of 21.05% with a V-OC of 1.23 V, where the V-OC deficit of 0.43 V is among the lowest values for inverted wide-bandgap PVSCs. Moreover, by stacking a semi-transparent perovskite top cell on a 1.1 eV Cu2ZnSn(S,Se)(4) (CZTSSe) bottom cell, a 22.27% PCE was achieved on a perovskite/CZTSSe four-terminal tandem solar cell, paving the way for all-solution-processed, low-cost, and efficient TSCs with mitigated energy loss in the wide-bandgap top cells.

• 单位
  南开大学; y