Reduced Graphene Oxide/O-MWCNT Hybrids Functionalized
with p‑Phenylenediamine as High-Performance MoS<sub>2</sub> Electrocatalyst Support for Hydrogen Evolution Reaction
Efficient hydrogen evolution through
water splitting at low overpotentials
is crucial to develop renewable energy technology, which depends on
the design of efficient and durable electrocatalysts composed of earth-abundant
elements. Herein, a highly and stable electrocatalyst for hydrogen
evolution reaction (HER) has been developed on the basis of MoS<sub>2</sub> on p-phenylenediamine (PPD)-functionalized reduced graphene
oxide/O-containing carbon nanotubes (rGO/O-MWCNT) hybrids via facile
and green hydrothermal process. Among the prepared catalysts, the
optimized MoS<sub>2</sub>/rGO/PPD/O-MWCNT with nanosized and highly
dispersed MoS<sub>2</sub> sheets provides a large amount of available
edge sites and the improved electron transfer in 3D conductive networks.
It exhibits excellent HER activity with a low overpotential of 90
mV and large current density of 47.6 mA·cm<sup>–2</sup> at 200 mV, as well as excellent stability in an acidic medium. The
Tafel slope of 48 mV·dec<sup>–1</sup> reveals the Volmer–Heyrovsky
mechanism for HER. Thus, this work paves a potential pathway for designing
efficient MoS<sub>2</sub>-based electrocatalysts for HER by functionalized
conductive substrates