Efficient Large-Area Quantum Cutting Photoconversion Films for Silicon Solar Cells on Photovoltaic Glass Using Knife Coating

Yb3+ doped perovskite nanocrystals (PNCs) serve as efficient photoconverters, exhibiting quantum cutting emission at ∼980 nm, which aligns precisely with the optimal response region of silicon solar cells (SSCs). However, severe nonradiative recombination caused by defects in the crystal lattice and film boundaries, along with limitations in small-scale film preparation, restricts their commercial application. Here, we used Ru3+ to mitigate lattice defects in CsPbCl3 PNCs and adjusted the quantum cutting luminescence, achieving a 175% photoluminescence quantum yield (PLQY). The results show that Ru3+ ions enter the perovskite lattice, fill lead vacancies, and passivate the lattice defects. Furthermore, cysteine effectively eliminates surface defects in PNCs by forming Pb–S bonds, resulting in films with a remarkable 117% PLQY, demonstrating strong photoconversion capabilities. Uniformly knife-coated on 20 × 20 cm2 photovoltaic glass, these films increased SSC efficiency from 21.45% to 23.15%. This study showcases a cost-effective photoconverter and a scalable coating method to boost the photovoltaic efficiency of large-area SSCs.