High‐Pressure‐Induced Comminution and Recrystallization of CH3NH3PbBr3 Nanocrystals as Large Thin Nanoplates

• DOI: 10.1002/adma.201705017
• Publication Date: 2017-11-27T06:38:21Z
• Authors: Tingting Yin; Yanan Fang; Wee Kiang Chong; Koh Teck Ming; Shaojie Jiang; Xianglin Li; Jer‐Lai Kuo; Jiye Fang; Tze Chien Sum; Timothy J. White; Jiaxu Yan; Ze Xiang Shen
• Keywords: Comminution; Recrystallization (geology); Nanocrystalline material

High pressure (HP) can drive the direct sintering of nanoparticle assemblies for Ag/Au, CdSe/PbS nanocrystals (NCs). Instead conventional nanocrystals, this study experimentally observes first time high-pressure-induced comminution and recrystallization organic-inorganic hybrid perovskite into highly luminescent nanoplates with a shorter carrier lifetime. Such novel response is attributed to unique structural nature perovskites under high pressure: during drastic cubic-orthorhombic transformation at ≈2 GPa, (301) crystal plane fully occupied by organic molecules possesses higher surface energy, triggering nanoslices along such plane. Beyond bulk perovskites, in which pressure-induced modifications on structures functional properties will disappear after release, pressure-formed variants, i.e., large (≈100 nm) thin (<10 nanoplates, are retained these exhibit simultaneous photoluminescence emission enhancing (a 15-fold enhancement photoluminescence) lifetime shortening (from ≈18.3 ± 0.8 ≈7.6 0.5 ns) releasing from 11 GPa. This NCs subsequent amorphization-recrystallization treatment offer possibilities engineering advanced specific properties.