Fabrication of a Water-Stripped Free-Standing Silver Nanowire Network as the Top Electrode for Perovskite Solar Cells

Recently, there has been significant interest in inorganic–organic hybrid perovskite solar cells (PSCs) due to their excellent photovoltaic performance. However, the fabrication of PSCs’ top metallic electrodes using thermal evaporation in a vacuum atmosphere significantly increases the manufacturing cost and restricts large-scale production. In this study, we propose a water separation method for the fabrication of free-standing films of silver nanowires (AgNWs) that can be easily stripped by using water and laminated onto perovskite devices as top electrodes in an ambient atmosphere. The electrodes composed of long AgNWs exhibit superior electrical properties compared to those composed of shorter ones. We have identified that the reduced performance of PSCs with AgNW electrodes is mainly attributed to the high oxide content on the surface of AgNWs and the insufficient contact between the AgNW networks and hole transport layers. To resolve these issues, we employed sodium borohydride reduction and polyethoxysiloxane incorporation techniques. Through these treatments, PSCs with AgNW electrodes achieved a power conversion efficiency of 15.64%. This performance surpasses that reported in the literature for PSCs with AgNW electrodes, demonstrating the effectiveness of our approach.