5.1 Quantum Dots
Quantum dots are nanometer-sized semiconductor crystals possessing exclusive
chemical and physical properties which is due to their highly compact structure.
Quantum dots possess narrow fluorescence emission bands with broad absorption
bands; making them excellent choice as optical transducers [85].
5.2 Metal and Metal Oxide Nanoparticles
Metal and metal oxide nanoparticles can be produced in various sizes and can be
easily functionalized to serve as a good sensor [87]. Colloidal solutions of gold and
silver nanoparticles, show unique colors based on the size of the colloidal nanomaterial; are stable biocompatible and extensively used in sensing applications [88].
Nano based metal oxides include oxides of iron, titanium, zirconium, cerium, zinc
and tin. Magnetic nanometal oxides of iron are popular owing to low toxicity,
economic, facile functionalization and easier separation process [89].
5.3 Carbon Based Nanomaterials
Recently, One and two dimensional materials, for instance Carbon nanotubes
(CNTs) and graphene its derivatives (graphene oxide, reduced graphene oxide) are
frequently employed for the fabrication of nano-based sensors owing to their high
surface area, mechanical strength, excellent electrical conductivity, and high thermal conductivity [90]. Graphene and derivatives are studied widely for fabrication
of sensors due to its high sensitivity to electronic perturbations on introduction of
any foreign molecule [84, 91].
5.4 Recent Studies Performed on Nanomaterials Based
Sensors
Xie et al. [92] developed a voltammetric sensor for dichlorophenol based on
beta-cyclodextrin functionalized boron-doped graphene composite aerogels. Rapid
mass transfer is ensured by high specific area, large pore volume and conductivity;
also uneven charge distribution is introduced by boron doping on graphene
enabling several active sites for catalytic oxidation of dichlorophenol. Liu et al. [93]
detected mercury (II) ions using high-fluorescent carbon dots originated from China
grass carp scales. The obtained carbon dots has large amount of cysteine-containing
sulfhydryl groups which enables to be used as specific fluorescence probe for
288
R. Soni et al.
Quantum dots are nanometer-sized semiconductor crystals possessing exclusive
chemical and physical properties which is due to their highly compact structure.
Quantum dots possess narrow fluorescence emission bands with broad absorption
bands; making them excellent choice as optical transducers [85].
5.2 Metal and Metal Oxide Nanoparticles
Metal and metal oxide nanoparticles can be produced in various sizes and can be
easily functionalized to serve as a good sensor [87]. Colloidal solutions of gold and
silver nanoparticles, show unique colors based on the size of the colloidal nanomaterial; are stable biocompatible and extensively used in sensing applications [88].
Nano based metal oxides include oxides of iron, titanium, zirconium, cerium, zinc
and tin. Magnetic nanometal oxides of iron are popular owing to low toxicity,
economic, facile functionalization and easier separation process [89].
5.3 Carbon Based Nanomaterials
Recently, One and two dimensional materials, for instance Carbon nanotubes
(CNTs) and graphene its derivatives (graphene oxide, reduced graphene oxide) are
frequently employed for the fabrication of nano-based sensors owing to their high
surface area, mechanical strength, excellent electrical conductivity, and high thermal conductivity [90]. Graphene and derivatives are studied widely for fabrication
of sensors due to its high sensitivity to electronic perturbations on introduction of
any foreign molecule [84, 91].
5.4 Recent Studies Performed on Nanomaterials Based
Sensors
Xie et al. [92] developed a voltammetric sensor for dichlorophenol based on
beta-cyclodextrin functionalized boron-doped graphene composite aerogels. Rapid
mass transfer is ensured by high specific area, large pore volume and conductivity;
also uneven charge distribution is introduced by boron doping on graphene
enabling several active sites for catalytic oxidation of dichlorophenol. Liu et al. [93]
detected mercury (II) ions using high-fluorescent carbon dots originated from China
grass carp scales. The obtained carbon dots has large amount of cysteine-containing
sulfhydryl groups which enables to be used as specific fluorescence probe for
288
R. Soni et al.