Abstract
Carbon quantum dots are sp2
/sp3
-hybridized carbon atoms with sizes ranging
from 2-10nm. They are zero-dimensional florescent nanomaterials that are less toxic,
more biocompatible and highly stable in nature. Carbon quantum dots have attracted
the attention of many research groups due to their novel characteristics and have found
several applications in industries. They are used in various scientific fields which
include synthesis and design of inexpensive biological and chemical sensors. Carbon
quantum dots have several uses in optical sensing, bio imaging, bio-sensing,
optoelectronics photovoltaic and photocatalysis because of their superior electronic,
optical, photocatalytic, up-conversion, photoluminescence and light harvesting
properties. Using CQD, a cost-effective and environmentally friendly method of
cleaning up environmental pollutants is introduced. They have lately been employed in
remediation experiments in place of or together with metal semiconductors due to their
optoelectronic features. Recently, the world has been facing serious threats due to
environmental contamination of various kinds, which has become more serious due to
lesser affordable means for treating it. Industrial waste, pesticides, heavy metal ions,
pharmaceutical waste and sewage are some of the commonly observed water
contaminants. Compared to the earlier studied forms of quantum dots, carbonaceous
quantum dots are the most prevalent ones and can be a better option. The goal of this
chapter is to explain the significance of carbonaceous quantum dots in environmental
remediation. In addition, the advantages of carbonaceous quantum dots over
conventional quantum dots, methods for synthesizing carbonaceous quantum dots (top
down and bottom up), their functionalization or doping to improve their selectivity and
sensitivity, their applications in various fields such as sensing, photocatalysis and biosensing have also been reviewed. By adding surface defects or interstitial states
between electron holes, these alterations have a major impact on the optical
characteristics of carbonaceous quantum dots. Additionally, the methods of removal of
pollutants have also been explored by physical, chemical conventional and biological
methods. Lastly, future perspectives and conclusion speculations have been considered.