class of carbonaceous material which are recently developed and attracted appreciable importance due to their superlative properties and significant applications in
different fields. By virtue of their unique optical, electronic, and efficient light
harvesting, tunable photoluminescence, and up-conversion property, carbon quantum dots displayed huge applications in bio-sensing, bio-imaging, drug delivery,
photocatalysis, photovoltaics and optoelectronics. Today, contamination of water is
one of the biggest and most alarming problems that demands an immediate solution,
and non-availability of economical method for water treatment makes it more
significant. The potential pollutants of water pollution are heavy metal ions, sewage,
pesticide, pharmaceutical waste, and industrial waste. The most abundant carbon as
photocatalytic nanomaterial could be a better choice among previously reported
conventional photocatalyst and quantum dots.
The book chapter aims to demonstrate top-down method and bottom-up method
for the fabrication of carbon quantum dots. Further, the basic mechanism of
photocatalysis, disadvantages of conventional quantum dots, classification of carbon
quantum dots, and the concept behind up-conversion phenomena were also
reviewed. The photocatalytic degradation and antimicrobial application of carbon
quantum dot-based photocatalyst were also explored. Lastly, conclusion and future
perspective were considered and speculated. The design of photocatalytic system
with high photo-efficiency is still challenging, and the area remains open to carry out
future research.
Keywords Carbon quantum dots · Graphene quantum dots · Photocatalyst ·
Nanocomposites · Up-conversion · Water purification
3.1 Introduction
The need of a promising approach to meet the global energy requirement of the
future generation as well decreasing environmental pollution by utilizing renewable
solar energy is the most prominent method. The idea of bringing out an effective
usage of solar energy makes scientists to explore such material which is capable of
both energy conversion and environmental pollutant degradation (Chandel et al.
2019; Gautam et al. 2017; Zhu et al. 2017). The semiconductor photocatalysts
become an evident material with immense potential for solving water pollution
(Singh et al. 2014; Raizada et al. 2017a; Shandilya et al. 2018a). Thus, various
semiconductor photocatalytic materials such as titanates (He et al. 2018; Kumar et al.
2019), vanadates (Adan et al. 2015), tungstates (Huang et al. 2014), zirconates (Chen
et al. 2015), chalcogenides (Nie and Zhang 2017), oxyhalides (Sharma et al. 2019a;
Priya et al. 2016a; Singh et al. 2016), ferrites (Sonu et al. 2019; Singh et al.
2019a, b), and borates (Huang et al. 2013) have been investigated. However, these
materials are associated with certain limitations like inefficient solar light harvesting
82
P. Shandilya et al.
different fields. By virtue of their unique optical, electronic, and efficient light
harvesting, tunable photoluminescence, and up-conversion property, carbon quantum dots displayed huge applications in bio-sensing, bio-imaging, drug delivery,
photocatalysis, photovoltaics and optoelectronics. Today, contamination of water is
one of the biggest and most alarming problems that demands an immediate solution,
and non-availability of economical method for water treatment makes it more
significant. The potential pollutants of water pollution are heavy metal ions, sewage,
pesticide, pharmaceutical waste, and industrial waste. The most abundant carbon as
photocatalytic nanomaterial could be a better choice among previously reported
conventional photocatalyst and quantum dots.
The book chapter aims to demonstrate top-down method and bottom-up method
for the fabrication of carbon quantum dots. Further, the basic mechanism of
photocatalysis, disadvantages of conventional quantum dots, classification of carbon
quantum dots, and the concept behind up-conversion phenomena were also
reviewed. The photocatalytic degradation and antimicrobial application of carbon
quantum dot-based photocatalyst were also explored. Lastly, conclusion and future
perspective were considered and speculated. The design of photocatalytic system
with high photo-efficiency is still challenging, and the area remains open to carry out
future research.
Keywords Carbon quantum dots · Graphene quantum dots · Photocatalyst ·
Nanocomposites · Up-conversion · Water purification
3.1 Introduction
The need of a promising approach to meet the global energy requirement of the
future generation as well decreasing environmental pollution by utilizing renewable
solar energy is the most prominent method. The idea of bringing out an effective
usage of solar energy makes scientists to explore such material which is capable of
both energy conversion and environmental pollutant degradation (Chandel et al.
2019; Gautam et al. 2017; Zhu et al. 2017). The semiconductor photocatalysts
become an evident material with immense potential for solving water pollution
(Singh et al. 2014; Raizada et al. 2017a; Shandilya et al. 2018a). Thus, various
semiconductor photocatalytic materials such as titanates (He et al. 2018; Kumar et al.
2019), vanadates (Adan et al. 2015), tungstates (Huang et al. 2014), zirconates (Chen
et al. 2015), chalcogenides (Nie and Zhang 2017), oxyhalides (Sharma et al. 2019a;
Priya et al. 2016a; Singh et al. 2016), ferrites (Sonu et al. 2019; Singh et al.
2019a, b), and borates (Huang et al. 2013) have been investigated. However, these
materials are associated with certain limitations like inefficient solar light harvesting
82
P. Shandilya et al.