Balancing Shading and Resistive Losses: 33% Efficient Perovskite/Silicon Tandem Solar Cells via Front-Electrode...

Perovskite/silicon tandem solar cells (PSTSCs) have broken the efficiency ceiling of single-junction solar cells, standing as a core technology for next-generation photovoltaics. Nevertheless, carrier losses at the front electrode, composed of transparent conductive films and metal grids, are often underestimated and hinder further performance improvement. Herein, we synergistically optimized the transparent electrode and front metal grid to reduce interfacial carrier loss while balancing optical shading and series resistance losses. Tungsten-doped indium oxide (IWO) with a lower work function and suitable energy alignment was adopted to replace conventional indium zinc oxide (IZO), improving carrier extraction and the device's fill factor (FF). Using our self-developed simulation tool, we quantified grid-induced power loss and systematically investigated how grid width and spacing affect photovoltaic performance. Guided by simulations, tandem cells with varied grid geometries were fabricated and tested. The optimized device delivered a champion power conversion efficiency (PCE) of 33.06% (certified 32.28%), with an FF of 80.87%, a short-circuit current density (J_SC) of 20.72 mA/cm^2, and an open-circuit voltage (V_OC) of 1.973 V. This work mitigates the understudied front-electrode carrier losses in PSTSCs and offers a feasible route toward scalable high-performance tandem photovoltaics.