The invention belongs to the technical field of photovoltaic solar materials, and particularly relates to a high-conversion-efficiency
perovskite precursor material and a preparation method thereof. The high-conversion-efficiency
perovskite precursor material is composed of phenyl
ammonium cesium composite cations,
metal halide, an additive, a nuclear auxiliary agent and a
solvent. By compounding phenylethyl
ammonium iodide and
cesium iodide, phenylammonium and cesium cations are introduced into
perovskite crystal lattices, organic-inorganic balance of the material is optimized, phenylammonium promotes formation of a quasi-two-dimensional structure, and damp-
heat stability is enhanced;
cesium ions fill A-site gaps, so that
crystal lattices are tighter, and the
thermal stability and the
photoelectric conversion efficiency are improved; the synergistic matching addition of the
metal halide realizes
band gap regulation and control and spectrum matching, and
quaternary ammonium salt adjusts
nucleation and
grain growth, so that a uniform
film structure is ensured, and defects are reduced; and
guanidine salt passivates defects after
crystal growth, stabilizes crystal lattices, and improves charge life and device efficiency.