Predicting Thermal Quenching in Inorganic Phosphors
Predicting Thermal Quenching in Inorganic Phosphors
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DOI：
10.1021/acs.chemmater.0c02231
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发表时间：
2020-07-28
影响因子：
8.6
通讯作者：
Ong, Shyue Ping
中科院分区：
文献类型：
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作者：
Amachraa, Mahdi;Wang, Zhenbin;Ong, Shyue Ping
磷光体转换发光二极管（LED）是固态照明的高效形式。磷光体的关键性能指标是其热猝灭（TQ），其是在操作期间在升高的温度下的发射损失百分比。在这项工作中，我们统一了两个流行的理论交叉和热电离机制到一个单一的预测模型TQ使用从头算分子动力学（AIMD）模拟，我们首次证明，TQ下的交叉机制是与当地的环境稳定性的激活剂。此外，通过考虑晶体场对热电离势垒的影响，我们表明，一个统一的模型可以预测实验TQ在29个已知的磷光体内的均方根误差为3.1- 7.6%。最后，我们提出了一种有效的拓扑方法，以快速筛选巨大的化学空间，发现新的，热稳定的磷光体。
Phosphor-converted light emitting diodes (LEDs) are a highly efficient form of solid-state lighting. A key performance metric of a phosphor is its thermal quenching (TQ), which is the percentage loss of emission at elevated temperatures during operation. In this work, we unify the two prevailing theories-the crossover and thermal ionization mechanisms-into a single predictive model for TQ Using ab initio molecular dynamics (AIMD) simulations, we demonstrate for the first time that TQ under the crossover mechanism is related to the local environment stability of the activator. Further, by accounting for the effect of the crystal field on the thermal ionization barrier, we show that a unified model can predict the experimental TQ in 29 known phosphors to within a root-mean-square error of similar to 3.1-7.6%. Finally, we propose an efficient topological approach to rapidly screen vast chemical spaces for the discovery of novel, thermally robust phosphors.