Carbon Dots Synthesized from Green Precursors with an Amplified Photoluminescence: Synthesis, Characterization, and Its Application

Abstract

The carbon dots (CDs) are widely applied in the field of bioimaging and sensing owing to their high photoluminescence, biocompatibility, small size (<10 nm), and low toxicity. Besides, CDs also possess the upconversion PL (UCPL) properties and are able to harvest long wavelength light. These properties help them in the photocatalytic degradation of organic pollutants when irradiated by natural sunlight. Nevertheless, the reported preparation method of CDs has met several limitations, such as limited spectral efficiency, low product yield, lack of size control, the use of toxic chemicals, and high temperature for experiments. For this reason, using green precursors to produce CDs such as orange juice, soy milk, chitosan, and orange waste peels caught numerous researchers’ attention. Abundant green precursors could be potentially used as a carbon source to produce value-added CDs. This book chapter will focus on the synthesis and characterization of carbon dots synthesized from green precursors via sustainable method. We will also report the application of carbon dots for the bioimaging, sensing, photocatalysis, and biomedicine.