BiVO4 is a promising photoanode material for the photoelectrochemical (PEC) oxidation of water; however, its poor charge transfer, transport, and slow surface catalytic activity limit the expected theoretical efficiency.
Development
of advanced materials for electrocatalytic and photocatalytic
water splitting is the key in utilization of renewable energy. In
the present work, we have synthesized MoS
2
nanoparticles
embedded over the graphene oxide (GO) and reduced graphene oxide (rGO)
layer for superior catalytic activity in the hydrogen evolution process
(HER). The nanocomposite materials are characterized using different
spectroscopic and microscopic measurements. A Tafel slope of ∼40
mV/decade suggested the Volmer–Heyrovsky mechanism for the
HER process with MoS
2
/GO composite as the catalyst, which indicated that electrochemical
desorption of hydrogen is the rate-limiting step. The small Tafel
slope indicates a promising electrocatalyst for HER in practical application.
MoS
2
/GO composite material has shown superior catalytic
behavior compared to that of MoS
2
/rGO composite material.
The HER catalytic activity of the catalysts is explored using scanning
electrochemical microscopy (SECM) using the feedback and redox competition
mode in SECM. The activation energy for HER activity was calculated,
and the values are in the range of 17–6 kJ/mol. The lower value
of activation energy suggested faster HER kinetics.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.