Synthesis and performance optimization of an integrated tandem beam splitting module with perovskite solar cells

The global energy transition demands increasingly efficient utilization of renewable energy sources. Solar spectral beam splitting technology, which directs photons of different wavelengths to photovoltaic and photothermal units respectively, offers a promising pathway toward comprehensive solar energy utilization. Perovskite solar cells, with their advantages of low cost, tunable bandgap, and high efficiency in short-wavelength bands, represent ideal photovoltaic components for such systems. This study investigated an integrated small-scale tandem beam splitting module combining thin-film interference splitters with perovskite solar cells. Performance characterization revealed that after beam splitting, the short-circuit current remained nearly unchanged, the open-circuit voltage decreased slightly, while both the fill factor and electrical efficiency increased modestly. To optimize beam splitting performance, a three-level, four-factor orthogonal experiment was conducted, examining the deposition rate and oxygen flow rate during deposition of TiO 2 and SiO 2 . Thickness correction factors were introduced to address splitting range shifts and improve beam splitting performance. The optimal parameters achieved an electrical efficiency of 16.23% and a thermal efficiency of 43.30%. Gradient experiments further revealed that both TiO 2 and SiO 2 correction factors follow a W-shaped trend as deposition rates vary, providing guidance for simplifying fabrication optimization. These findings contribute to advance solar energy utilization from single-function power generation toward comprehensive photovoltaic/photothermal synergy.