Carbon Dots as a Fluorescent Probe for Appraising Morphology‐Dependent Free‐Radical‐Scavenging Properties of CuO Nanostructures.

Free radical scavenging property of different ligand directed nanostructures of CuO (rod‐, sphere, flower‐, and star‐shaped) prepared through aqueous based chemical precipitation route using various carboxylic acids (viz. tartaric acid, citric acid and acetic acid) have been investigated using N,S co‐doped carbon dots (NSCDs) as a novel fluorescent probe which is validated through diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging assay and EPR study. The rod shaped nanostructures having the highest negative surface potential and lowest BET surface area compared to other morphologies, were found to show the highest radical scavenging ability which was corroborated with the maximum decrease of the DPPH absorption peak in UV‐vis spectra, largest attenuation of the DPPH free radical signal in EPR intensity and the maximum quenching of the fluorescent intensity of the NSCDs probe. [ABSTRACT FROM AUTHOR]