Amplifying Surface Energy Difference toward Anisotropic Growth of All‐Inorganic Perovskite Single‐Crystal Wires for Highly Sensitive Photodetector

Abstract

AbstractIt is a great challenge to directly grow super long all‐inorganic perovskite monocrystalline wires due to the weak surface energy difference among the low index facets. Here, a one‐pot solution process to grow the aspect ratio over 105 of monocrystalline CsPbBr3 perovskite wires (PWs) and yield up to 70% is reported. A chemical potential dependent surface energy difference amplification strategy is proposed to regulate the surface energy of growing and grown surfaces accordingly to the anisotropic growth of CsPbBr3. The anisotropic growth of wires is derived from the regulation of anti‐solvent diffusion kinetic and the mass transfer kinetic control of the metal halide salts. This experiment demonstrates a 50 times amplification of surface energy difference. As‐produced PWs present a high photodetection responsivity up to 4923 A W−1, external quantum efficiency exceeding 13 784%, and detectivity over 3.6 × 1013 Jones. This work not only reveals the mechanism of surface energy dominated anisotropic growth for CsPbBr3 PWs, but also elucidates the important role of kinetics regulation during the growth process, which may open a new window for the low‐dimensional crystal growth of ionic compounds.