Recent advances in Cr3+-doped near-infrared phosphors: preparation, luminescence, and LED applications

Abstract

Near-infrared (NIR) phosphors constitute a significant class of luminescent materials for light-emitting diodes (LEDs). Recently, considerable research efforts in this active field have been devoted to the development of Cr³⁺-doped oxide, fluoride, and chloride phosphors for NIR luminescence emission, in which the unique d–d transition enables their tunable luminescence properties suitable for diverse LED applications such as plant growth lighting, bioimaging, night vision, non-destructive testing, and compositional analysis. This review article provides a comprehensive overview of recent advances in Cr³⁺-doped NIR phosphors, with emphasis on their detailed preparation methods, luminescence properties, and application potential in LED devices. Additionally, significant research challenges are outlined to guide the development of Cr³⁺-activated NIR phosphors, supported by a comprehensive list of representative references.