TuningSpacer Interactionvia Br-Substitution Positionfor High-Efficiency and Stable 2D Ruddlesden–Popper PerovskiteSolar Cells

Engineering notes

Engineering notes will be added by the Power for Solar editorial team.

Chinese explanation / 中文解读

中文解读待补充：本站会优先为光伏效率、钙钛矿太阳能电池、储能技术、太阳能热利用、BIPV、并网技术等高价值论文补充中文说明。

Original abstract

Quasi-two-dimensional (quasi-2D) Ruddlesden–Popper (RP) perovskites with layered structures are promising photovoltaic materials owing to their improved environmental stability, but their power conversion efficiencies (PCEs) still lag behind those of state-of-the-art 3D perovskites. Here, we investigate the bromine-substitution position effect of aromatic spacers in quasi-2D RP perovskite solar cells by comparing the meta- and para-substituted spacer molecules <i>m</i>-BrPEAAA and <i>p</i>-BrPEAAA. We show that para substitution induces a larger molecular dipole, strengthens spacer-framework interaction, and promotes more ordered crystallization. As a result, the <i>p</i>-BrPEAAA-based quasi-2D RP perovskite film exhibits improved crystallinity, prolonged carrier lifetime, and more favorable electronic structure. The corresponding device achieves a champion PCE of 20.16%, outperforming its meta-substituted counterpart (18.91%). In addition, the para-substituted system shows improved thermal and moisture stability. This work highlights bromine substitution-position engineering as an effective strategy for regulating spacer-framework interaction and improving the efficiency and stability of quasi-2D RP perovskite solar cells.

Links and sources

Comments