Single-Source Vapor Deposition of Quantum-Cutting Yb³⁺:CsPb(Cl_1–<i>x</i>Br_<i>x</i>)₃and Other Complex Metal-Halide Perovskites

Abstract

Metal-halide semiconductors exhibit attractive properties for a host of applications including photovoltaics, solid-state lighting, and photodetection. Among the remarkable recent developments is the discovery of extraordinarily high photoluminescence quantum yields in Yb3+-doped inorganic lead-halide perovskites. Although all previous research and development of such quantum-cutting materials has involved solution-phase preparation, particularly as colloidal nanocrystals, such methods can introduce both processing and technical challenges that limit the scope of accessible compositions, morphologies, and scaled-up applications. Here, we demonstrate a scalable single-source vapor deposition (SSVD) method for depositing high-quality conformal thin films of complex metal-halide perovskites, including doped perovskites, over large areas at high deposition rates. Focusing on quantum-cutting Yb3+:CsPb(Cl1–xBrx)3, we demonstrate large-area deposition of films with photoluminescence quantum yields as high as 183%, starting from single-source powders prepared mechanochemically from solid ionic precursors. We also prepare thin films of the solar absorber material (FA0.81MA0.14Cs0.05)Pb(Cl0.02Br0.14I0.84)3 to illustrate the generality of this SSVD method. These results demonstrate a promising approach to high-throughput vapor processing of metal-halide coatings for photonic and optoelectronic applications.