Control on the Long-Range Ordering of Perovskite Nanocrystal Superlattices via Thermal Regulation of Nanoconfined Water

Abstract

Temperature governed the one-step liquid-phase formation of CsPbBr3 nanocrystal superlattices in a nonpolar medium through trace-water retention and ligand organization. A lower temperature produced larger but less abundant superlattice domains, an intermediate temperature favored ordered assembly, and a higher temperature suppressed long-range order, yielding dispersed nanocrystals. Small-angle X-ray scattering and molecular dynamics simulations suggested that temperature-dependent water retention and localization underpinned superlattice ordering. The ordered superlattices exhibited distinct photoluminescence features.