[3PS-069]
High-Efficiency All-Perovskite Tandem Solar Cells Enabled by Vertical Homogeneity Control
발표자허수빈 (한양대학교)
연구책임자박희준 (한양대학교)
Abstract
All-perovskite tandem solar cells are promising platform for high-efficiency photovoltaics, yet their performance is limited by non-radiative recombination at perovskite/charge-transport layer interfaces. These losses arise from defects and energy-level mismatches within each sub-cell and are further intensified by residual strain induced by thermal expansion mismatch between perovskite and substrates.[1] Here, we present a dual-interface optimization strategy using alkyl diammonium interlayers. The effectiveness strongly depended on the alkyl chain length of the interlayers. Interfacial modification suppressed non-radiative recombination by reducing defect density and residual strain.[2] Consequently, wide- and low-bandgap single-junction devices achieve efficiencies of 20.5% and 22.4%, respectively. An all-perovskite tandem device delivers a power conversion efficiency of 27.5% and retains over 90% of its initial performance after 500h under ambient conditions.