Co-doped 1T-MoS2 microspheres embedded in N-doped reduced graphene oxide for efficient electrocatalysis toward hydrogen and oxygen evolution reactions

The development of an efficient, bifunctional, and affordable catalyst has emerged as a valuable approach in electrocatalysis because it can enhance the conductivity, charge transfer capability, and number of active sites of the catalyst. In this study, we synthesis flower-like morphologies of 1T-phase cobalt (Co)-doped molybdenum disulfide (MoS2) embedded on nitrogen-doped reduced graphene oxide (N-rGO) using a facile hydrothermal technique. Owing to this configuration, the optimal Co0.18/1T-Mo0.82S2@N-rGO catalyst exhibits remarkable activity toward the oxygen evolution reaction, with a low overpotential of 243 mV and a Tafel slope of 75 mV/dec at 10 mA/cm2. The catalyst also demonstrates excellent performance in the hydrogen evolution reaction with an overpotential of 142 mV and a Tafel slope of 48 mV/dec to afford a current density of −10 mA/cm2 in basic media, which are comparable to platinum on carbon and iridium dioxide, along with excellent stability. To perform overall water splitting, assembled Co0.18/1T-Mo0.82S2@N-rGO (+//-) cell requires only 1.51 V to achieve 10 mA/cm2. This study illustrates the beneficial effect of Co doping on the synthesized flower-shaped MoS2, formation of the 1T phase, and the performance of N-rGO as a conductive network, which holds significant potential in the field of electrocatalysis.