Dual Interfacial Design Enables Efficient and Stable Semitransparent Wide‐Bandgap Perovskite Solar Cells With Scalable‐Coated Silver Nanowire Contact for Tandem Applications

ABSTRACT Semitransparent perovskite solar cells (PSCs) hold great potential for applications in aesthetic building facades and top‐illuminated tandem devices. Indium tin oxide is currently the frequently used top transparent contact, which would degrade the underlying perovskites during sputter process. Here, we report low‐temperature, scalable solution‐processed silver nanowires (AgNWs) as top window electrodes for fabricating efficient and stable semitransparent PSCs. As a decisive step, an impermeable SnO 2 thin film deposited by atomic layer deposition (ALD) is applied to prevent chemical reactions between AgNWs and halides of perovskites. In parallel, the molecular absorption of propylenediamine iodine (PDADI) on perovskite surface, instead of forming two‐dimensional (2D) perovskite capping layer, is found to effectively passivate the perovskite surface, which simultaneously leads to remarkably enhanced thermal stability, thus affording the processing window for ALD‐SnO 2 deposition. Eventually, the prepared semitransparent PSCs with a bandgap of 1.71 eV achieve a champion efficiency of 17.5%, being the highest efficiency for semitransparent PSCs with AgNWs top contacts. On these bases, we constructed a four‐terminal perovskite/copper indium gallium diselenide (CIGS) tandem cell, giving a state‐of‐the‐art efficiency of 26.85%.