Biogenic Carbon Quantum Dots: Synthesis and Applications.

The new class of nanomaterials termed carbon dots: a quasi-spherical nanoparticle having a size less than 10 nm, possesses some unique characteristics like good aqueous solubility, colloidal stability, resistance to photobleaching, and fluorescence tunability, resulting in the unfolding of their various properties and their usage in different applications. Materials that are naturally derived or produced by living organisms are termed 'biogenic'. Over the past few years, there has been a gradual increase in the use of naturally derived materials in synthesizing carbon dots. Green precursors or biogenic materials are of low cost, readily available, renewable, and environmentally benign. Most importantly, they provide essential benefits not found in synthesized carbon dots. This review focuses on the use of biogenic materials for the synthesis of biogenic carbon dots developed in the past five years. It also briefly explains different synthetic protocols used, along with some significant findings. Thereafter, an overview of the use of biogenic carbon dots (BCDs) in different applications like chemo and biosensors, drug delivery, bioimaging, catalysis and energy applications, etc., is discussed. Thus biogenic carbon dots are future sustainable materials that are now fast replacing conventional carbon quantum prepared from other sources.