In-situ synthesis of organic-inorganic hybrid thin film of PEDOT/V2O5 as hole transport layer for polymer solar cells

•Hybrid film of PEDOT/V2O5 was obtained via an in-situ synthesis method.•A higher PCE of 3.76% is achieved using PEDOT/V2O5, which increased by 8% than that of the regular PEDOT:PSS device.•Devices with PEDOT/V2O5 show better stability. Here, an organic-inorganic hybrid thin film of PEDOT/V2O5 complex was successfully obtained via an in-situ synthesis method. In detail, PEDOT buffer layer was prepared by in-situ oxidative polymerization. Then, a layer of V2O5 nanoparticles was deposited on it. V2O5 nanoparticles can closely combine with PEDOT and modifying the surface defects of PEDOT. For the control polymer solar cells (PSCs) with a PEDOT:PSS hole transport layer (HTL), a power conversion efficiency (PCE) of 3.50% is obtained. Encouragingly, a higher PCE of 3.76% is achieved for the cell using the as-prepared PEDOT/V2O5 as the HTL, which increased by 8% than that of the control device. Furthermore, the devices with PEDOT/V2O5 show a better stability than the control devices using PEDOT:PSS as HTL. The results indicate that PEDOT/V2O5 is an excellent HTL for efficient and stable PSCs.