All-inorganic halide perovskites (IHP), CsPbX₃ (X = Cl, Br, I) exhibiting efficient optical emissions within the spectral range of 410 to 730 nm are potential candidates for many optoelectronic devices. Anion alloying of these IHPs is expected to achieve tunable emission wavelength covering the entire visible spectrum. Here, we developed a two-step chemical vapor deposition (CVD) process for growing quaternary IHP CsPbX₃ (X = Cl/Br and Br/I) alloys. By exploiting the fast diffusion of halide anions in IHPs, the alloy composition can be precisely controlled by the growth time of the respective layers once the growth of the individual ternary IHP is optimized. Hence complexities in the multi-parameter optimization in the conventional CVD growth of quaternary alloys can be mitigated. Using this process, we synthesized single crystalline, homogeneous and thermally stable CsPbCl₃(_1−X)Br_3x and CsPbBr₃(_1−X)I_3x perovskites alloy microplates and demonstrated continuously tunable emission covering the spectrum from 428 to 715 nm by varying the halide compositions in the alloys. These alloy microplates also exhibit room temperature amplified spontaneous emissions (ASE) along with strong photonic discharges from the microplate’s edges and hence are potentially useful as a gain medium as well as optical cavities for emissions with wavelengths covering the visible spectrum.

在410至730 nm光谱范围内表现出有效光发射的全无机卤化物钙钛矿（IHP），CsPbX ₃（X = Cl，Br，I）是许多光电器件的潜在候选者。这些IHP的阴离子合金化有望实现覆盖整个可见光谱的可调发射波长。在这里，我们开发了两步化学气相沉积（CVD）工艺来生长四元IHP CsPbX ₃（X = Cl / Br和Br / I）合金。通过利用卤化物阴离子在IHP中的快速扩散，一旦各个三元IHP的生长得到优化，就可以通过各层的生长时间精确控制合金成分。因此，可以减轻四元合金常规CVD生长中多参数优化的复杂性。使用此方法，我们合成了单晶，均质且热稳定的CsPbCl ₃（_{1- X}）Br _{3 x}和CsPbBr ₃（_{1- X}）I _{3 x}钙钛矿合金微板，并证明了通过改变合金中的卤化物组成，可连续发射的光谱范围从428到715 nm。这些合金微孔板还具有室温放大的自发辐射（ASE），以及来自微孔板边缘的强光子放电，因此有可能用作增益介质以及用于波长覆盖可见光谱的光腔。