Enhanced Photovoltaic Performance in Silicon/PEDOT:PSS Hybrid Solar Cells via Hydrogen Pretreatment of PEDOT:PSS

Silicon/PEDOT:PSS hybrid solar cells have attracted attention due to their simple fabrication process. While liquid-phase treatments are widely employed to optimize the conductivity of PEDOT:PSS, gas-phase pretreatment strategies remain largely underexplored. Herein, we introduce a gas-phase hydrogen pretreatment strategy that effectively screens the negative charges on sulfonate groups, thereby attenuating the Coulombic interactions between PEDOT+ and PSS− chains and enhancing film conductivity. Following a 24-h hydrogen pretreatment, the fill factor (FF) increases from 61 to 65.8%, resulting in a power conversion efficiency (PCE) improvement from 12.15% to 13.61%. Further synergy with epoxy resin optimization elevates the PCE to 14.36% and significantly bolsters environmental stability: the devices retain 60% and 70% of their initial PCE after 200 h of storage at 80 °C and −12 °C, respectively. These results show that hydrogen pretreatment of PEDOT:PSS is a successful and feasible approach for Si/PEDOT:PSS hybrid solar cells, contributing to the development of solar cell technology.