6 research outputs found
In situ electrochemical transformation of Ni<sub>3</sub>S<sub>2</sub> and Ni<sub>3</sub>S<sub>2</sub>-Ni from sheets to nanodisks: towards efficient electrocatalysis for Hydrogen Evolution Reaction (HER)
Transition metal sulphides have been viewed as alternatives to platinum based electrocatalysts for HER. Herein, we report the preparation of Ni3S2 in conjunction with Ni in a novel nanosheet morphology and verified its performance for HER. During cyclic polarization, exotic morphological transformation of Ni3S2-Ni from nanosheets to nanodisks has been noted. This change is accompanied with initial increase in over-potential that passed through maxima (∼ 100 mV above the starting potential) and decreased to ∼ 50 mV below the starting value. Enhanced electrocatalytic activity due to the morphological changes from sheets to nanodisks has been attributed to the formation of more number of exposed edge-planes known to promote HER. Kinetic analysis based on Tafel slope displayed by this composite is comparable to that of Pt based catalysts
Interaction between Quantum Dots of CdTe and Reduced Graphene Oxide: Investigation through Cyclic Voltammetry and Spectroscopy
Cyclic
voltammetry has been used to investigate the interaction
between reduced graphene oxide (r-GO) and CdTe quantum dots (Q-CdTe).
For that, the composite of Q-CdTe with r-GO (r-GO-CdTe) was prepared
by carrying out the reduction of graphene oxide and the synthesis
of Q-CdTe simultaneously, in a single bath. r-GO-CdTe was characterized
by UV–visible, steady state fluorescence, time-resolved fluorescence,
X-ray diffraction (XRD), Raman, and transmission electron microscopy
(TEM). Cyclic voltammetry was employed to determine the quasi-particle
gap and band edge parameters of Q-CdTe and r-GO-CdTe. The blue shifts
in the quasi-particle gap of r-GO-CdTe have been attributed to the
strong interaction of graphene with CdTe. These interactions were
further verified by time-resolved fluorescence and Raman spectroscopy
which suggested strong electronic coupling between Q-dots and graphene