Carbon dots composite luminescent materials: Design, optical properties, and applications

Carbon dots (CDs), as emerging carbon nanomaterials, have attracted significant attention from researchers because of their unique optical properties. However, the stability of single CDs is poor, their functionality is limited, and their fluorescence and phosphorescence are prone to aggregation quenching and affected by nonradiative transitions. In recent years, to address these limitations, researchers have developed CDs composites luminescent materials, greatly expanding the range of applications of CDs. In this review, we review the research progress of CDs composites from three aspects: design and preparation, optical properties, and applications. In particular, the methods for designing and preparing CDs composites, including surface modification, matrix assistance, and energy transfer strategies, are summarized. These methods enable the realization of long-wavelength, multicolor, stimuli-responsive, and long lifetime luminescence properties in CDs composites. Then, we introduce the applications of CDs composites in the photoelectric field, sensing, biological imaging, information security and identification. Finally, we conclude by discussing the challenges and future development directions of CDs composites.