Poly(methyl methacrylate) embedded perovskite films for improving solar cell performance

Semi-transparent photovoltaics are promising technologies to be applied for building-integrated elements and alternative windows. Notably, organometallic halide perovskite solar cells that have shown unprecedented power conversion efficiencies (PCEs) are highly attractive for integration as solar windows in buildings because of its low-cost manufacturing and tunable transparency in the visible regime. Here, we demonstrate an approach to fabricate void-passivated transparent perovskite films by utilizing a poly(methyl methacrylate) (PMMA) as a framework for crystal growth. The semitransparent perovskite film (average visible transmittance, AVT of ˜ 35.2%) is prepared from PbICl layer assisting sequential inter-diffusion process in which PMMA (PMMA dissolved in chlorobenzene) is added into CH3NH3I (MAI) solution. The presence of PMMA in perovskite films have a negligible effect on transparency, and the coverage and crystallinity of perovskite films are improved. Intensity-modulated photocurrent spectroscopy (IMPS) and time-correlated single photon counting (TCSPC) characterization further demonstrate that the PMMA embedded perovskite films have better carrier transport and enhanced carrier extraction rate. The semitransparent perovskite film based photovoltaic device with PMMA presents 15.46% efficiency with less hysteresis, which is mainly attributed to increased Jsc.