@article {44660, title = {Synthesis of ecofriendly fluorescent carbon dots and their biomedical and environmental applications}, journal = {Materials Technology}, volume = {33}, year = {2018}, month = {JAN}, pages = {672-680}, abstract = {

Green Synthesis of nanoparticles is an emerging field with enormous advantages over conventional synthesis methods. Herein we have reported a green method for the preparation of water soluble polydisperse carbon dots (c-dots) from Cocos nucifera frond pinnae by a modified version of the {\textquoteleft}single step hydrothermal carbonization{\textquoteright}. C-dots having blue emission were obtained with this method and we further evaluated the effect of metal ions interactions on c-dots, as a sharp decrease in photoluminescence was observed. The synthesized c-dots were found bioactive against B.subtilis, M. smegmatis and S. aureus as determined by the well diffusion assay. We also explored nanotheranostic applications of c-dots as biosensor matrix in DNA hybridization sensor for pancreatic cancer and in bioimaging of cancer cells. This study demonstrated that c-dots can be explored for numerous biomedical and environmental applications in a variety of fields owing to the cost effective synthesis, biocompatibility and excellent physico-chemical properties.

}, keywords = {Carbon dots, differential pulse voltammetry, DNA hybridization sensor, green synthesis, Pancreatic Cancer}, issn = {1066-7857}, doi = {10.1080/10667857.2018.1492683}, author = {Joshi, Preeti Nigam and Mathias, Anjelica and Mishra, Abhishek} } @article {47438, title = {Autophagy and unique aerial oxygen harvesting properties exhibited by highly photocatalytic carbon quantum dots}, journal = {Carbon}, volume = {181}, year = {2021}, month = {AUG}, pages = {16-27}, type = {Article}, abstract = {

Plastic pollution is a serious threat to the environment as they are not bio-degradable. Herein using waste-polyethylene, we report two inter-related important findings. First that they can be converted economically and completely into highly photocatalytic carbon quantum-dots (CQDs) using H2O2\ as a residue-free oxidant in an acid medium, and they have the ability to enrich a reaction medium with an extraordinary amount of molecular oxygen harvested from the air so that no separate oxygen source is needed while carrying out facile photocatalytic\ oxidation reactions. Second, when they are not performing any photocatalytic reaction, they exhibit self-sensitized photo-oxidation to convert themselves completely to CO2\ in the presence of sunlight, a phenomenon that we term as {\textquoteleft}CQD-autophagy{\textquoteright} by drawing parallels to the death of useless-cells in the body. Such extinction from the reaction media is unique as no other material is known to do so and advantageous because the removal of carbon-dots from a solution is rather inefficient from an industry-viewpoint due to their high solubility. Instead, the inexpensive CQDs can be discarded casually with the notion that they will gradually get eliminated from the environment.

}, keywords = {Carbon dots, Oxygen-enrichment, Photocatalytic oxidation, Self-sensitized photo-oxidation}, issn = {0008-6223}, doi = {10.1016/j.carbon.2021.04.054}, author = {Mondal, Sanjit and Vinod, C. P. and Gautam, Ujjal K.} } @article {48987, title = {Facile microwave synthesis of Zinc Ferrite@NCDs for photocatalytic degradation of fluoroquinolone antibiotics}, journal = {Materials Chemistry and Physics}, volume = {314}, year = {2024}, month = {FEB}, type = {Article}, abstract = {

Zinc ferrite (ZnFe2O4) composites have attracted growing interest in photocatalytic water purification. Herein, the hybrids of zinc ferrite and nitrogen-doped carbon dots (ZnF@x\%NCDs) were synthesized via facile micro-wave synthesis. X-ray diffraction and Raman characterization confirm the formation of the spinel structure, and elemental composition has been analyzed by X-ray photoelectron spectroscopy. The photocatalytic activity of ZnF@x\%NCDs was evaluated via the decomposition of ciprofloxacin and norfloxacin under visible light illumination. We noted that 20 \% weight loading of NCDs led to the highest (similar to 79.2 \%) ciprofloxacin (CIP) degradation. Diffuse reflectance measurements demonstrate the reduction of the band gap in composites ZnF@20\%NCDs (1.91 eV) compared with bare ZnF (2.03 eV); moreover, the hybridization of zinc ferrites with NCDs results in enhanced photocurrent density and surface area. The effect of experimental parameters, including the role of photocatalyst dosage, pH value, and initial concentration of pollutants on the degradation of CIP, have also been investigated.

}, keywords = {Carbon dots, Ciprofloxacin degradation, Norfloxacin degradation, Photocatalysis, Zinc Ferrite}, issn = {0254-0584}, doi = {10.1016/j.matchemphys.2023.128823}, author = {Kaushal, Neha and Sarraf, Sonu and Basu, Aviru Kumar and Mishra, Sunita and Saha, Avishek} }