Controlled Size Growth of Thermally Stable Organometallic Halide Perovskite Microrods: Synergistic Effect of Dual-Doping, Lattice Strain Engineering, Antisolvent Crystallization, and Band Gap Tuning Properties

摘要

Organometallic halide perovskites, as the light-harvesting material, have been extensively used for cost-effective energy production in high-performance perovskite solar cells, despite their poor stability in the ambient atmosphere. In this work, methylammonium lead iodide, CH_(3)NH_(3)PbI_(3), perovskite was successfully doped with KMnO_(4) using antisolvent crystallization to develop micrometer-length perovskite microrods. Thus, the obtained KMnO_(4)-doped perovskite microrods have exhibited sharp, narrow, and red-shifted photoluminescence band, as well as high lattice strain with improved thermal stability compared to undoped CH_(3)NH_(3)PbI_(3). During the synthesis of the KMnO_(4)-doped perovskite microrods, a low boiling point solvent, anhydrous chloroform, was employed as an antisolvent to facilitate the emergence of controlled-size perovskite microrods. The as-synthesized KMnO_(4)-doped perovskite microrods retained the pristine perovskite crystalline phases and lowered energy band gap (～1.57 eV) because of improved light absorption and narrow fluorescence emission bands (fwhm < 10 nm) with improved lattice strain (～4.42 × 10~(–5)), Goldsmith tolerance factor (～0.89), and high dislocation density (～5.82 × 10~(–4)), as estimated by Williamson–Hall plots. Thus, the obtained results might enhance the optical properties with reduced energy band gap and high thermal stability of doped-perovskite nanomaterials in ambient air for diverse optoelectronic applications. This study paves the way for new insights into chemical doping and interaction possibilities in methylamine-based perovskite materials with various metal dopants for further applications.