Abstract:

In the mesoscale perovskite material system, perovskite magic sized clusters (PMSCs) have great development prospects and application potential in the field of emerging optoelectronic devices due to their excellent semiconductor properties, such as narrow emission spectral band, high color purity, precise wavelength tunability, uniform particle size distribution, simple solution processing and synthesis process. However, the mesoscale PMSCs are easy to generate perovskite quantum dots (PQDs) with large size during the synthesis process, which is difficult to meet the needs of practical applications. To solve this problem, a simple and controllable ligand-assisted reprecipitation (LAPR) method was used to synthesize inorganic hybrid mesoscale perovskite materials of CsPbBr₃ PMSCs, CsPbBr₃ PMSCs/CsPbBr₃ PQDs mixtures and CsPbBr₃ PQDs with different luminescence properties by adjusting the ratio of valeric acid (VA) to oleylamine (OAm) surface ligands. The optical properties, morphological structure, stability and mesoscale structure evolution mechanism of the PQDs and PMSCs were studied and analyzed in detail. It is found that the ratio of surface synergistic passivation ligands VA to OAm is the key to whether the reaction can generate pure-phase CsPbBr₃ PMSCs. Moreover, when the surface passivation effect of VA and OAm ligands is optimal, it is easier to generate mesoscale pure-phase CsPbBr₃ PMSCs with excellent luminescence properties.

Key words: mesoscale, inorganic hybrid perovskite, cluster, nanostructure, synthesis, stability, luminescence properties

摘要：

近年来，介尺度钙钛矿材料体系中钙钛矿魔幻尺寸团簇（PMSCs）材料因具有优异的半导体特性而在新兴光电器件领域极具潜力。然而，介尺度PMSCs容易在合成过程中生成尺寸较大的介尺度钙钛矿量子点（PQDs），难以满足实际应用的需求。本研究采用配体辅助再沉淀（LAPR）方法，通过调节戊酸（VA）和油胺（OAm）配体比例制备了不同发光性质的无机杂化介尺度钙钛矿材料CsPbBr₃ PMSCs、CsPbBr₃ PMSCs/CsPbBr₃ PQDs混合物和CsPbBr₃ PQDs，研究并分析了PQDs和PMSCs的光学性质、形貌结构、稳定性和介尺度结构演变机理。研究发现，表面协同钝化配体VA和OAm的比例是反应能否生成介尺度纯相CsPbBr₃ PMSCs的关键。而且，当VA和OAm配体的表面钝化效果越佳越易生成发光性质优异的纯相CsPbBr₃ PMSCs。

关键词: 介尺度, 无机杂化钙钛矿, 团簇, 纳米结构, 合成, 稳定性, 发光性质