Insertion of metal cations into hybrid organometallic halide perovskite nanocrystals for enhanced stability: eco-friendly synthesis, lattice strain engineering, and defect chemistry studies

Abstract

In this work, we developed a facile and environmentally friendly synthesis strategy for large-scale preparation of Cr-doped hybrid organometallic halide perovskite nanocrystals. In the experiment, methylammonium lead bromide, CH3NH3PbBr3, was efficiently doped with Cr3+ cations by eco-friendly method at low temperatures to grow crystals via antisolvent-crystallization. The as-synthesized Cr3+ cation-doped perovskite nanocrystals displayed similar to 45.45% decrease in the (100) phase intensity with an enhanced Bragg angle (2 theta) of similar to 15.01 degrees compared to similar to 14.92 degrees of pristine perovskites while retaining their cubic (221/Pm-cm, ICSD no. 00-069-1350) crystalline phase of pristine perovskites. During synthesis, an eco-friendly solvent, ethanol, was utilized as an antisolvent to grow nanometer-sized rod-like crystals. However, Cr3+ cation-doped perovskite nanocrystals display a reduced crystallinity of similar to 67% compared to pristine counterpart with similar to 75% crystallinity with an improved contact angle of similar to 72 degrees against water in thin films. Besides, as-grown perovskite nanocrystals produced crystallite size of similar to 48 nm and a full-width-at-half-maximum (FWHM) of similar to 0.19 degrees with an enhanced lattice-strain of similar to 4.52 x 10(-4) with a dislocation-density of similar to 4.24 x 10(14) lines per m(2) compared to pristine perovskite nanocrystals, as extracted from the Williamson-Hall plots. The as-obtained stable perovskite materials might be promising light-harvesting candidates for optoelectronic applications in the future.