From highly graphitic to amorphous carbon dots: A critical review

Abstract

Graphitic and amorphous C-dots share common characteristics in their photoluminescence behavior. However, the graphitic dots have a lead as electrocatalyst for fuel cells, sensitizers, and electron acceptors for solar cells.The emergence of carbogenic nanoparticles (C-dots) as a new class of photoluminescent (PL) nanoemitters is directly related to their economical preparation, nontoxic nature, versatility, and tunability. C-dots are typically prepared by pyrolytic or oxidative treatment of suitable precursors.While the surface functionalities critically affect the dispersibility and the emission intensity of C-dots in a given environment, it is the nature of the carbogenic core that actually imparts certain intrinsic properties. Depending on the synthetic approach and the starting materials, the structure of the carbogenic core can vary from highly graphitic all the way to completely amorphous. This critical review focuses on correlating the functions of C-dots with the graphitic or amorphous nature of their carbogenic cores. The systematic classifi cation on that basis can provide insights on the origins of their intriguing photophysical behavior and can contribute in realizing their full potential in challenging applications.Keywords : luminescence ; nanostructure ; carbonization REVIEW DISCUSSION POINT ▪ C-dots set an example that low-cost, non-toxic materials can effectively supplant highly engineered, yet toxic compounds in challenging applications.

Detection of metronidazole in honey and metronidazole tablets using carbon dots‐based sensor via the inner filter effect

“…Furthermore, XRD pattern was collected to characterize the crystalline nature of the CDs (see Figure c). The pattern presented several peaks centered at 20.4°, 27.3°, 31.77°, 45.3°, 56.2°, 66.2°, 75.2°, corresponding to the peaks of the acid fuchsin (JCPDS: 09‐0819) without lattice structure in the CDs, indicating that the resultant CDs have an amorphous nature …”

Carbon Quantum Dot as Electron Transporting Layer in Organic Light Emitting Diode

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Tetraphenylethene–diyne hybrid nanoparticles from Glaser-type dispersion polymerization

“…1) due to their high stability, low cytotoxicity and their tuneable photoluminescence (PL) properties. [2][3][4] However, their preparation oen requires harsh conditions. 2,3 In addition to carbon nanoparticles, conjugated polymer nanoparticles (CPNs) are also interesting counterparts to QDs due to their low cytotoxicity and tuneable optical properties for electronic devices and biological applications.…”