16
2 Water Splitting Reactions and Nanotechnology
and anode, and the mixture of FeSO 4 ·7H 2 O, Na 2 SO 4 , and cetyl trimethylammonium bromide (CTAB) was used as the electrolyte. By passing the 10 mA current
through the electrochemical cell, αFe 2 O 3 /Ni electrode was obtained. Afterward, it
was immersed in the solution of H 2 PtCl 6 for impregnation deposition and was later
soaked in NaBH 4 for the reduction of Pt. The product was washed with deionized (DI)
water. These flower-like Pt quantum dot ornamented αFe 2 O 3 nanosheets were characterized with TEM, XRD, field-emission scanning electron microscope (FESEM),
and X-ray photoelectron spectroscopy (XPS) [8].
Graphene quantum dots also have favorable electrocatalytic effects in a water splitting reaction. In an investigation, a group of researchers have shown the water splitting abilities of graphene hydrogel/B-doped graphene quantum dots (GH-BDGQD).
These quantum dots have high porosity, large surface area, numerous active sites,
improved ion diffusion, and mass transport. Because of this the GH-BDGQD exhibits
advanced trifunctional electrocatalytic ability including hydrogen liberation, oxygen
liberation, and oxygen reduction along with the greater stability as compared to the
available commercial counterparts [9].
Z-scheme system of black and red phosphorous quantum dots is capable of
achieving water splitting reaction for evolution of hydrogen in the absence of sacrificial agents. In a study, wet-chemistry path was followed for the fabrication of
Z-scheme system of black/red phosphorus quantum dots (BRPQD). These quantum
dots were fabricated by the conversion of red phosphorous into black phosphorus
with reflux reaction between red phosphorous and ethylenediamine. After which
phase transformation reaction was allowed to occur and the product was centrifuged
at 6000 rpm in order to remove large particles. Later on, Tyndall effect of the particle
was observed which indicated fabrication of the stable quantum dots. The synthesized
product was characterized with TEM, XPS, UV–Vis spectrometer, UV photoelectron spectroscopy (UPS), time-resolved transient absorption spectroscopy (TAS),
and inductively coupled plasma atomic emission spectroscopy (ICP-AES) [10].
A successful research has suggested solenoid nitridation reduction process for
the generation of α-MoC 1−x quantum dots encased in carbon doped with nitrogen
(α-MCNCQD). The frog egg-shaped quantum dots were to promote H 2 evolution
in water splitting reaction at all pH levels, with the overpotential of 118 mV, and
10 mA cm
−2 was obtained in alkaline solutions. The α-MCNCQD also depicted
rapidly increasing current density (which was much greater than the commercially
available Pt/C electrocatalysts). These quantum dots showed equally promising
results in neutral and acidic solutions. α-MCNCQD were prepared by mixing of urea
and ammonium molybdate tetrahydrate under the temperature-controlled reduction.
Nitrogen atmosphere was provided during the thermal process, which helps in the
achievement of N-doping of the mixture; afterward, the product was sonicated and
α-MCNCQD were achieved. The prepared quantum dots were characterized with
XRD, XPS, FESEM, and TEM and the composition of the catalyst was determined
with ICP-AES [11].
2 Water Splitting Reactions and Nanotechnology
and anode, and the mixture of FeSO 4 ·7H 2 O, Na 2 SO 4 , and cetyl trimethylammonium bromide (CTAB) was used as the electrolyte. By passing the 10 mA current
through the electrochemical cell, αFe 2 O 3 /Ni electrode was obtained. Afterward, it
was immersed in the solution of H 2 PtCl 6 for impregnation deposition and was later
soaked in NaBH 4 for the reduction of Pt. The product was washed with deionized (DI)
water. These flower-like Pt quantum dot ornamented αFe 2 O 3 nanosheets were characterized with TEM, XRD, field-emission scanning electron microscope (FESEM),
and X-ray photoelectron spectroscopy (XPS) [8].
Graphene quantum dots also have favorable electrocatalytic effects in a water splitting reaction. In an investigation, a group of researchers have shown the water splitting abilities of graphene hydrogel/B-doped graphene quantum dots (GH-BDGQD).
These quantum dots have high porosity, large surface area, numerous active sites,
improved ion diffusion, and mass transport. Because of this the GH-BDGQD exhibits
advanced trifunctional electrocatalytic ability including hydrogen liberation, oxygen
liberation, and oxygen reduction along with the greater stability as compared to the
available commercial counterparts [9].
Z-scheme system of black and red phosphorous quantum dots is capable of
achieving water splitting reaction for evolution of hydrogen in the absence of sacrificial agents. In a study, wet-chemistry path was followed for the fabrication of
Z-scheme system of black/red phosphorus quantum dots (BRPQD). These quantum
dots were fabricated by the conversion of red phosphorous into black phosphorus
with reflux reaction between red phosphorous and ethylenediamine. After which
phase transformation reaction was allowed to occur and the product was centrifuged
at 6000 rpm in order to remove large particles. Later on, Tyndall effect of the particle
was observed which indicated fabrication of the stable quantum dots. The synthesized
product was characterized with TEM, XPS, UV–Vis spectrometer, UV photoelectron spectroscopy (UPS), time-resolved transient absorption spectroscopy (TAS),
and inductively coupled plasma atomic emission spectroscopy (ICP-AES) [10].
A successful research has suggested solenoid nitridation reduction process for
the generation of α-MoC 1−x quantum dots encased in carbon doped with nitrogen
(α-MCNCQD). The frog egg-shaped quantum dots were to promote H 2 evolution
in water splitting reaction at all pH levels, with the overpotential of 118 mV, and
10 mA cm
−2 was obtained in alkaline solutions. The α-MCNCQD also depicted
rapidly increasing current density (which was much greater than the commercially
available Pt/C electrocatalysts). These quantum dots showed equally promising
results in neutral and acidic solutions. α-MCNCQD were prepared by mixing of urea
and ammonium molybdate tetrahydrate under the temperature-controlled reduction.
Nitrogen atmosphere was provided during the thermal process, which helps in the
achievement of N-doping of the mixture; afterward, the product was sonicated and
α-MCNCQD were achieved. The prepared quantum dots were characterized with
XRD, XPS, FESEM, and TEM and the composition of the catalyst was determined
with ICP-AES [11].