Halide perovskite nanocrystal arrays: Multiplexed synthesis and size-dependent emission
Jingshan S. Du, Donghoon Shin, Teodor K. Stanev, Chiara Musumeci, Zhuang Xie, Ziyin Huang, Minliang Lai, Lin Sun, Wenjie Zhou, Nathaniel P. Stern, Vinayak P. Dravid, Chad A. Mirkin
Abstract
Halide perovskites have exceptional optoelectronic properties, but a poor understanding of the relationship between crystal dimensions, composition, and properties limits their use in integrated devices. We report a new multiplexed cantilever-free scanning probe method for synthesizing compositionally diverse and size-controlled halide perovskite nanocrystals spanning square centimeter areas. Single-particle photoluminescence studies reveal multiple independent emission modes due to defect-defined band edges with relative intensities that depend on crystal size at a fixed composition. Smaller particles, but ones with dimensions that exceed the quantum confinement regime, exhibit blue-shifted emission due to reabsorption of higher-energy modes. Six different halide perovskites have been synthesized, including a layered Ruddlesden-Popper phase, and the method has been used to prepare functional solar cells based on single nanocrystals. The ability to pattern arrays of multicolor light-emitting nanocrystals opens avenues toward the development of optoelectronic devices, including optical displays.