Abraham Joselyn Elizabeth, Balachandran Manoj
Materials Science Research Laboratory, Department of Physics and Electronics, CHRIST (Deemed To Be University), Bengaluru, 560029, Karnataka, India.
J Fluoresc. 2022 May;32(3):887-906. doi: 10.1007/s10895-022-02915-4. Epub 2022 Mar 18.
Fluorescent carbon dots (CDs) have acquired growing interest from different areas over decades. Their fascinating property of tunable fluorescence by changing the excitation wavelength has attracted researchers worldwide. Understanding the mechanisms behind fluorescence is of great importance, as they help with the synthesis and applications, significantly when narrowed down to applications with color-tunable mechanisms. But, due to a lack of practical and theoretical information, the fluorescence mechanisms of CDs remain unknown, preventing the production of CDs with desired optical qualities. This review focuses on the PL mechanisms of carbon dots. The quantum confinement effect determined the carbon core, the surface and edge states determined by various surface defects and the connected functional/chemical groups on the surface/edges, the molecular state solely determined the fluorophores in the interior or surface of the CDs, and the Crosslink Enhanced Emission Effect are the currently confirmed PL mechanisms.
几十年来，荧光碳点（CDs）在不同领域引起了越来越多的关注。它们通过改变激发波长实现可调谐荧光的迷人特性吸引了全球的研究人员。了解荧光背后的机制非常重要，因为这有助于其合成和应用，特别是在涉及颜色可调机制的应用中。但是，由于缺乏实际和理论信息，碳点的荧光机制仍然未知，这阻碍了具有所需光学性质的碳点的生产。本综述重点关注碳点的光致发光机制。量子限制效应决定了碳核，各种表面缺陷以及表面/边缘上连接的官能团/化学基团决定了表面和边缘状态，分子状态仅决定了碳点内部或表面的荧光团，而交联增强发射效应是目前已确认的光致发光机制。
