Affiliation:
1. Yunnan Key Laboratory of Electromagnetic Materials and Devices National Center for International Research on Photoelectric and Energy Materials Yunnan Key Laboratory of Carbon Neutrality and Green Low‐carbon Technologies Innovation Center of Carbon Neutrality School of Materials and Energy Yunnan University Kunming 650091 China
2. Fujian Provincial Key Laboratory of Electrochemical Energy Storage Materials College of Chemistry Fuzhou University Fuzhou 350108 China
Abstract
AbstractEu3+‐activated red‐emitting inorganic phosphors have been favored highly for their classical 5D0→7FJ (J = 0, 1, 2, 3, 4) emissions. However, the fatal drawbacks of poor luminous efficacy and weak 5D0→7F4 transition persist, resulting in the ongoing challenge of achieving far‐red emission. This research reports series of highly efficient far‐red phosphors LnTeBO5 (Ln = La3+, Y3+, Gd3+):Eu3+ with anomalously strong 5D0→7F4 transition, resulting from the distorted square antiprism [Ln/EuO8]. Both the luminous efficacy and thermal stability can be greatly enhanced via the simple composition variation. [Ln/EuO8] square antiprism‐triggered 5D0→7F2,4 transitions are elucidated in depth, acquiring ultra‐high luminous efficacy (IQE = 95%, EQE = 40%, and AE = 42%) and near‐zero thermal quenching (99%@150°C and 98%@200°C). Subsequently, the versatile utilizations in indoor lighting, plant growth lighting, and security ink are illustrated. This finding establishes a deep understanding for constructing high‐quality far‐red phosphors via the Eu3+‐centered structural units of square antiprism.
Funder
National Natural Science Foundation of China