Recent Advances in Chromium‐Doped Near‐Infrared Luminescent Materials: Fundamentals, Optimization Strategies, and Applications

Abstract

Development of chromium‐doped luminescent materials is pertinent to many emerging applications, ranging from agriculture, food industry to noninvasive health monitoring. The fundamental importance of chromium‐activated luminescent materials in the field of optics and biomedicine makes the rapid development of novel materials and relevant applications. Herein, the recent advances on the luminescence principle and photoluminescence (PL) optimization for Cr ³⁺‐activated luminescent materials together with their potential applications are reviewed. The different types of most recently developed Cr ³⁺‐doped luminescent materials and the design principles are systematically summarized. The associations between crystal structure and near‐infrared (NIR) PL properties, as well as performance‐evaluating parameters are introduced with the examples of known NIR emitting phosphors, which will be helpful to explore future NIR luminescent materials. Based on crystal field control, site engineering, and electron–phonon coupling, several efficient strategies for optimizing luminescence performances including bandwidth, thermal stability, and quantum efficiency of Cr ³⁺‐doped NIR luminescent materials are proposed. Then, potential applications in the fields of food analysis, night vision, information encryption, and optical sensors are surveyed. Finally, the challenges of promising Cr ³⁺‐doped luminescent materials are proposed.