Study of multi-faceted CoS2 introduced graphene aerogel hybrids via chemical approach for an effective electrocatalytic water splitting

The present article reports the synthesis of hybrid structure along with non-precious cobalt-disulfide. A simple hydrothermal method was used to fabricate multi-faceted CoS2 introduced graphene aerogels. Studies on electrocatalytic activity showed that the presence of CoS2 facets along with graphene aerogel played a prominent role in the enhancement of proton reduction to hydrogen gas. The CoS2/graphene aerogel hybrid sample exhibits extremely low overpotential (160 mV vs. RHE), and high current density for HER in acidic solution. The activity enhancement can be attributed to increasing the active electrochemical surface area of graphene aerogel and faceted particles inside the 3D matrix of graphene. Furthermore, the CoS2/graphene hybrid retained its high activity even after 1000 cycles of cyclic voltammetry scans, signifying longer stability under acidic condition. The results suggest that CoS2/graphene aerogel hybrids show their potential application to hydrogen evolution reaction. [Display omitted] •A cost-effective and simple method for the synthesis of multifaceted CoS2/graphene structures.•Growth and uniform dispersion of the CoS2/graphene structures were controlled through a facile hydrothermal process.•High activity of the composite CoS2/graphene (160 mV) sample as that of the pristine graphene aerogel (279 mV).