Surface functionality and formation mechanisms of carbon and graphene quantum dots
| Autor: | Ryan M. Robinson, Cynthia Melendrez, Abraham Wolcott, Özgür Keleş, Folarin Erogbogbo, Dennis Nordlund, Anuja Bokare |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Graphene Mechanical Engineering Photodetector chemistry.chemical_element Nanotechnology 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences XANES 0104 chemical sciences Electronic Optical and Magnetic Materials Nanomaterials law.invention X-ray photoelectron spectroscopy chemistry law Quantum dot Materials Chemistry Electrical and Electronic Engineering 0210 nano-technology Carbon |
| Zdroj: | Diamond and Related Materials. 110:108101 |
| ISSN: | 0925-9635 |
| DOI: | 10.1016/j.diamond.2020.108101 |
| Popis: | Graphene quantum dots (GQDs) and Carbon dots (C-dots) have been widely studied in recent years due to their structural and optoelectrical properties. These properties have prompted the exploration of the role of these carbon-based materials in many potential applications. This includes solar cells, photodetectors, bioimaging, sensors, batteries and drug delivery. These properties and applications of GQDs and C-dots are highly dependent on their size, shape and surface functionality. In this work, GQDs and C-dots mixtures have been synthesized by an inexpensive wet chemical method by varying the synthesis temperature from 85°, 100° to 115 °C. The surface functionalities of the synthesized carbon-based materials were investigated by several analytical methods. We discovered a higher degree of oxidation at higher temperatures. The mechanism of formation of different sized GQDs and C-dots with different functionalities have been explained with the help of XPS and NEXAFS analysis. The influence of size and surface functionalities on the optical properties of these nanomaterials is analyzed by UV–Vis and PL spectroscopic techniques. This study demonstrates that physicochemical properties of GQDs and C-dots can be controlled by changing the synthesis temperature. |
| Databáze: | OpenAIRE |
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