Insights into Mechanism of CsPbBr 3 Nanocrystal Interfacial Modifier in Perovskite Solar Cells

During the past decade,organic-inorganic hybrid perovskite solar cell(PSC)has attracted great attention in the photovoltaic field 1,2.As the third-generation solar cell,PSC in laboratory has already achieved certified power conversion efficiency(PCE)exceeding 25％.The superb photovoltaic performance of PSC is attributed to the unique optoelectronic properties of organic-inorganic halide perovskite light absorption layer,including low exciton binding energy,high absorption coefficients,and outstanding carrier mobility3,4.Hence,the quality of perovskite film plays a decisive role in the photovoltaic performance of PSC.Defects are inevitably formed on the surface and inside of polycrystalline perovskite film during the conventional preparation methods.It's widely acknowledged that defects are the recombination centers of photogenerated electrons and holes,resulting in the loss of useful photogenerated charges 5,6.Therefore,decreasing the charge loss is advantageous to improving the PCE of PSC.