2.3 Nanoparticles and Water Splitting Reactions
17
2.3 Nanoparticles and Water Splitting Reactions
Nanoparticles have been the integral part of water splitting reaction for evolution
of H 2 since the introduction of the reaction for gas liberation. Several studies have
reported the use of nanoparticles for the generation of H 2 by splitting of water. Ni
and Ru core–shell nanoparticles ornamented on carbon nanosheets (Ni@Ru/CNS-x)
have depicted superior photocatalytic activity in splitting of water for liberation of H 2
at all pH levels. Ni@Ru/CNS-x were prepared by facile by using metal organic framework (MOF) as a sacrificial precursor wet-chemistry technique. The Ni@Ru/CNS-x
nanoparticles were characterized by SEM and TEM. The prepared catalysts exhibited 10 mA cm
−2 HER for low overpotential of 20.1 mV in alkaline environment
which is far superior than the commercially available Pt/C and RuO 2 [12].
In an investigation conducted by Yu et al. exo-solution of Ag nanoparticles on
AgTaO 3 -SrTiO 3 is reported as remarkable plasmonic photocatalysts for splitting of
water. Polymers of AgTaO 3 and SrTiO 3 salts were prepared by standard polymerized
complex method. The brown resin obtained was grounded to powder and pressed
into pellets which were calcined in muffle furnace, and the material was powdered
again. Afterward, the Ag nanoparticles were grown on the freshly prepared powders
by making the suspension of the solid powder in ethylene glycol. For the termination of the reaction, the mixture was transferred to the ice water. The product
thus obtained was centrifuged several times and rinsed with DI water and dried for
24 h. The prepared material was characterized with XRD, TEM, XPS, and UV–Vis
spectrophotometer. Photoelectrochemical analysis of these nanoparticles has shown
improved photocatalytic activity and better charge separating conditions [13].
In a recent study, a super-fast synthesis technique of CoS nanoparticles has been
reported for the HER by splitting of water. Chen et al. have reported ~7 ms hightemperature treatment method chalcogenide nanoparticles. For the preparation of
these nanoparticles, cobalt acetate and thiourea were dissolved in DI water. Later on,
graphene oxide ink was added to the solution and the mixture was sonicated and was
casted on the glass plate. The graphene sheet was removed after an hour and was
annealed in Ar atmosphere and was later on subjected to the thermal shock of about
2000 K which instantly cut the film into small particles. The prepared nanoparticles
were characterized with SEM, TEM, XPS, and XRD. CoS and graphene core–shell
nanoparticles depict excellent water splitting activity of 10 mA cm
−2 at a low overpotential of ~1.77 V without any loss in the activity for continuous 60-h operation
[14].
2.4 Nanotubes and Water Splitting Reactions
Nanotubes of different materials are also proven to be very efficient in a variety of
water splitting mechanisms. For instance, crystalline nanotube of TiO 2 . It is one of
the most classic materials to improve the efficiency of the water splitting reactions
17
2.3 Nanoparticles and Water Splitting Reactions
Nanoparticles have been the integral part of water splitting reaction for evolution
of H 2 since the introduction of the reaction for gas liberation. Several studies have
reported the use of nanoparticles for the generation of H 2 by splitting of water. Ni
and Ru core–shell nanoparticles ornamented on carbon nanosheets (Ni@Ru/CNS-x)
have depicted superior photocatalytic activity in splitting of water for liberation of H 2
at all pH levels. Ni@Ru/CNS-x were prepared by facile by using metal organic framework (MOF) as a sacrificial precursor wet-chemistry technique. The Ni@Ru/CNS-x
nanoparticles were characterized by SEM and TEM. The prepared catalysts exhibited 10 mA cm
−2 HER for low overpotential of 20.1 mV in alkaline environment
which is far superior than the commercially available Pt/C and RuO 2 [12].
In an investigation conducted by Yu et al. exo-solution of Ag nanoparticles on
AgTaO 3 -SrTiO 3 is reported as remarkable plasmonic photocatalysts for splitting of
water. Polymers of AgTaO 3 and SrTiO 3 salts were prepared by standard polymerized
complex method. The brown resin obtained was grounded to powder and pressed
into pellets which were calcined in muffle furnace, and the material was powdered
again. Afterward, the Ag nanoparticles were grown on the freshly prepared powders
by making the suspension of the solid powder in ethylene glycol. For the termination of the reaction, the mixture was transferred to the ice water. The product
thus obtained was centrifuged several times and rinsed with DI water and dried for
24 h. The prepared material was characterized with XRD, TEM, XPS, and UV–Vis
spectrophotometer. Photoelectrochemical analysis of these nanoparticles has shown
improved photocatalytic activity and better charge separating conditions [13].
In a recent study, a super-fast synthesis technique of CoS nanoparticles has been
reported for the HER by splitting of water. Chen et al. have reported ~7 ms hightemperature treatment method chalcogenide nanoparticles. For the preparation of
these nanoparticles, cobalt acetate and thiourea were dissolved in DI water. Later on,
graphene oxide ink was added to the solution and the mixture was sonicated and was
casted on the glass plate. The graphene sheet was removed after an hour and was
annealed in Ar atmosphere and was later on subjected to the thermal shock of about
2000 K which instantly cut the film into small particles. The prepared nanoparticles
were characterized with SEM, TEM, XPS, and XRD. CoS and graphene core–shell
nanoparticles depict excellent water splitting activity of 10 mA cm
−2 at a low overpotential of ~1.77 V without any loss in the activity for continuous 60-h operation
[14].
2.4 Nanotubes and Water Splitting Reactions
Nanotubes of different materials are also proven to be very efficient in a variety of
water splitting mechanisms. For instance, crystalline nanotube of TiO 2 . It is one of
the most classic materials to improve the efficiency of the water splitting reactions