Heating-insulating and semitransparent inorganic perovskite solar cells

Heat-insulating semitransparent solar cells, with power-generating and energy-saving functions, have attracted wide attention due to their potential applications in building and automobile integrated photovoltaics. However, it is challenging to simultaneously improve the power conversion efficiency (PCE) and average visible transmittance (AVT) in the wavelength of 400–800 nm for multifunctional semitransparent solar cells. Moreover, as an essential requirement for practical application, the thermal stability is still lacking. In this work, CsPbI₂Br inorganic perovskite with high bandgap and superior thermal stability is selected as absorber, combined with ultrathin silver top electrodes for charge collection and infrared reflector, composing the heat-insulating and semitransparent perovskite solar cells (PSCs). By virtue of dual-function ultrathin silver top electrodes, combined with high-index MoO_x to further improve visible transmittance, the semitransparent PSCs exhibit PCE of >11% with high AVT of >21%, as well as an outstanding infrared ray energy rejection of >72%. Moreover, the semitransparent inorganic PSCs exhibit superior thermal stability than the organic-inorganic counterparts, remaining 75% and 65% of initial PCE after aging at 85 °C for 200 h in N₂ and 105 h in air, respectively. This work paves the way toward realizing high-performance and thermal stable heat-insulating semitransparent solar cells, which greatly enhances their integration into various further applications.