Breaking 1.7 V Open Circuit Voltage in Large Area Transparent Perovskite Solar Cells Using Interfaces Passivation

Efficient semi-transparent solar cells can extend the adoption of photovoltaics beyond standard utility-scale, commercial, or residential applications. Halide perovskites are particularly suitable in this respect owing to their tunable bandgap. The main drawbacks in the development of transparent perovskite solar cells are the high open-circuit voltage (V_oc) deficit and the difficulties in depositing high-quality thin films over large area substrates, given the low solubility of bromide and chloride precursors. In this work, passivation strategies are developed for the high bandgap Br perovskite able to reduce charge recombination and consequently improve the V_oc. The study demonstrates 1 cm² perovskite solar cells with V_oc up to 1.73 V (1.83 eV Quasi Fermi Level Splitting) and a PCE of 8.1%. The average visible transmittance (AVT) exceeds 70% by means of a bifacial light management and a record light utilization efficiency (LUE) of 5.72 is achieved. Moreover, the potential use of the technology is evaluated toward Internet of Things (IoT) application owing to a bifaciality factor of 87% along with 17% PCE under indoor lighting. Finally, the up-scaling is demonstrated by fabricating 20 cm² active area modules with PCE of 7.3% and V_oc per cell up to 1.65 V.