Quantum wells and superlattices are key building blocks in the semiconductor industry, normally fabricated using epitaxial growth techniques, such as vapor phase epitaxy, metalorganic chemical vapor deposition and molecular beam epitaxy. However, these complicated preparation processes, as well as their high cost, limit their extensive applications. It is essential to develop a simple solution process for building superstructures. Here, we demonstrate an ion exchange strategy for synthesizing an all-inorganic superlattice cesium lead bromide/layered double hydroxides (CsPbBr₃/LDH) in solution. At room temperature, the perovskite ions diffuse into the interlayer of LDH and assemble into layered perovskite with various thicknesses. Compared with traditional organic-inorganic hybrid perovskite superlattice, the all-inorganic perovskite superlattice CsPbBr₃/LDH has weak quantum confinement, which exhibits narrow emission line-widths of 20 nm, high quantum yields of 55%, and radiative lifetimes of several ns. Our findings offer a new route to synthesize novel perovskite superlattices and enrich the perovskite supercrystal platform for electronics, photonics and optoelectronics devices.

量子阱和超晶格是半导体行业的关键组成部分，通常使用外延生长技术制造，例如气相外延、金属有机化学气相沉积和分子束外延。然而，这些复杂的制备过程以及高昂的成本限制了它们的广泛应用。开发一个简单的上层建筑解决方案流程至关重要。在这里，我们展示了一种在溶液中合成全无机超晶格溴化铯铅/层状双氢氧化物（CsPbBr ₃ /LDH）的离子交换策略。在室温下，钙钛矿离子扩散到LDH的层间并组装成不同厚度的层状钙钛矿。与传统的有机-无机杂化钙钛矿超晶格相比，全无机钙钛矿超晶格CsPbBr ₃ /LDH具有弱量子限制，具有20 nm的窄发射线宽、55%的高量子产率，几个纳秒的辐射寿命。我们的研究结果为合成新型钙钛矿超晶格提供了一条新途径，丰富了电子、光子和光电子器件的钙钛矿超晶平台。