Enhanced electrochemical performance of NbSe2/rGO nanocomposite for oxygen evolution reaction (OER)

Abstract

Globally, there are significant concerns about the steadily rising energy demand and depletion of conservative fuels. Water electrolysis provides hydrogen and oxygen, which can be used as a fuel with a highest energy conversion efficiency and gravimetric energy density. In future, hydrogen fuel will take the place of conventional fossil fuels, which are polluting the environment. For a greater range of energy generation devices, the highly appropriate, affordable electrocatalyst for OER is significant. In present work, a NbSe₂/rGO nanocomposite was fabricated via hydrothermal process for OER electrochemical studies under 1.0 M KOH. The fabricated materials were verified by Raman spectroscopy, scanning electron microscopy (SEM), X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray. Because of its distinct shape, nanocomposite has more surface area, which results in more active pores with lots of potential for transfer of charge and prolonged material stability. The surface area of NbSe2/rGO nanocomposite determined through BET was 51 m²/g, i.e., higher than that of NbSe₂, thus providing greater number of active sites for OER performance. The electrocatalytic performance results represented that pure NbSe₂ nanosheets revealed a higher Tafel slope (51 mV/dec), conversely, NbSe₂/rGO nanocomposite represented lower Tafel slope (36 mV/dec) respectively and efficient durability for 60 h with minor alternation in current density for long time period. As a consequence, the created nanocomposite proves to be an effective electrocatalyst for OER and energy conversion applications.

Graphical Abstract