Development of halide perovskite composite with thermal-conductive microstructure for high power LED

混合卤化物钙钛矿由于其优异的性能在照明和光伏器件中的应用受到了广泛的关注。了解混合卤化物钙钛矿的相偏析机理对抑制光电器件的性能退化具有重要意义。在此，我们研究了混合卤化物钙钛矿纳米晶体（NCs）在不受外界因素（氧气、水分和压力）影响的情况下使用玻璃封装，其具有优异的光稳定性，可以防止相偏析。通过监测NCs在玻璃基体中的结构演变，实时观察了混合卤化物钙钛矿中共存的相偏析和非晶化现象。结果表明，热致局部温度升高对混合卤化物钙钛矿NCs的相偏析起主导作用。回收过程是由非晶混合卤化物相的自发结晶驱动的。明确了成分偏析（混合）与结构无序（有序）之间的动态平衡过程，使我们对混合卤化物钙钛矿的可逆相偏析机理有了更好的认识。

Mixed-halide perovskites have attracted great attention in applications of lighting and photovoltaic devices due to their excellent properties. Understanding the phase segregation mechanism of mixed-halide perovskite has significance for suppressing the performance degradation of optoelectronic devices. Herein, we investigate the mixed-halide perovskite nanocrystals (NCs) in isolation from the external factors (oxygen, moisture, and pressure) using glass encapsulation, which shows excellent photostability against phase segregation. By monitoring the structural evolution of the NCs in glass matrices, the coexisting phase segregation and amorphization of mixed-halide perovskites are observed in real-time. The results show that thermal-induced local temperature increase plays a dominant role in the phase segregation of mixed-halide perovskite NCs. The recovery process is driven by the spontaneous crystallization of the amorphous mixed-halide phase. The clarified dynamic equilibrium process between the compositional segregation (mixing) and structural disorder (order) gives us a better insight into the reversible phase segregation mechanism of mixed-halide perovskite.