Abstract
We have investigated the effects of the methylammonium bromide (MABr) content of the precursor solution on the properties of wide-bandgap methylammonium lead tribromide (MAPbBr(3)) perovskite solar cells (PSCs). In addition, the anti-solvent process for fabricating MAPbBr(3) perovskite thin films was optimized. The MAPbBr(3) precursor was prepared by dissolving MABr and lead bromide (PbBr(2)) in N,N-dimethylformamide and N,N-dimethyl sulfoxide. Chlorobenzene (CB) was used as the anti-solvent. We found that both the morphology of the MAPbBr(3) layer and the PSCs performance are significantly affected by the MABr content in perovskite precursor solution and anti-solvent dripping time. The best-performing device was obtained when the molar ratio of MABr:PbBr(2) was 1:1 and the CB drip time was 10 s. The best device exhibited a power conversion efficiency of 7.58%, short-circuit current density of 7.32 mA·cm(-2), open-circuit voltage of 1.30 V, and fill factor of 79.87%.