Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 2 de 2
Filter
Add more filters










Database
Main subject
Language
Publication year range
1.
Luminescence ; 38(7): 845-866, 2023 Jul.
Article in English | MEDLINE | ID: mdl-35419945

ABSTRACT

Carbon quantum dots (CQDs) are promising carbonaceous nanomaterials fortuitously discovered in 2004. CQDs are the rising stars in the nanotechnology ensemble because of their unique properties and widespread applications in sensing, imaging, medicine, catalysis, and optoelectronics. CQDs are notable for their excellent solubility and effective luminescence and, as a result, they are also known as carbon nanolights. Many strategies are used for the efficient and economical preparation of CQDs; however, CQDs prepared from waste or green sustainable methods have greater requirements due to their safety and ease of synthesis. Sustainable chemical strategies for CQDs have been developed, emphasizing green synthetic methodologies based on 'top-down' and 'bottom-up' approaches. This review summarizes many such studies relevant to the development of sustainable methods for photoluminescent CQDs. Furthermore, we have emphasized recent advances in CQDs' photoluminescence applications in chemical and biological fields. Finally, a brief overview of synthetic processes using the green source and their associated applications are tabulated, providing a clear understanding of the new optoelectronic materials.


Subject(s)
Quantum Dots , Quantum Dots/chemistry , Carbon/chemistry , Luminescence , Catalysis
2.
J Phys Condens Matter ; 32(40): 405202, 2020 Jun 18.
Article in English | MEDLINE | ID: mdl-32554870

ABSTRACT

The photocatalytic activity (PCA) of ZnO@Ag nanocomposites for different concentrations of Ag is reported. Dumbbells shaped zinc oxide (ZnO) nanostructures with silver (Ag) nanoparticles were synthesized by a simple chemical colloidal method. The as synthesized nanocomposites (without any heat treatment) were used for optical and photocatalytic studies. The FESEM analysis shows that the composite catalysts are composed of ZnO dumbbells coated with spherical Ag nanoparticles. UV-visible spectrum of ZnO@Ag photocatalysts shows a strong absorption band of ZnO at 380 nm with a plasmonic peak of Ag at 440 nm. The PL emission intensity of the composites varies with Ag concentration and has a minimum for the catalyst containing 13.7% of Ag. A possible growth mechanism of ZnO nanostructures with hexagonal cross-section has been proposed. Photocatalytic property of the as synthesized ZnO and ZnO@Ag catalysts was studied by investigating the degradation of methylene blue (MB) dye on exposure to UV-visible radiation. A relatively faster degradation of the dye was observed for ZnO@Ag composites as compared to pure ZnO, showing an improved photocatalytic behavior in the visible region. We proposed a possible mechanism for the enhancement in photocatalytic activity of Ag coated ZnO photocatalysts.

SELECTION OF CITATIONS
SEARCH DETAIL
...