Hexagonal nickel selenide nanoflakes decorated carbon fabric: An efficient binder-free water loving electrode for electrochemical water splitting

Abstract

In recent times, production of hydrogen by water splitting has introduced a new era to sustainable energy storage and fuel cell technology. To simplify the design of the water splitting devices and enhance its activity, a new thrust to develop low cost, stable, earth abundant electrocatalysts which can participate in both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is the need of the hour. Here, we report the two-step hydrothermally synthesized nickel diselenide hexagonal flakes deposited on carbon cloth (NiSe2/CC) which has acted as efficient electrocatalyst for both HER and OER in alkaline medium. Necessary characterizations are performed. The NiSe2 sheet comprises small hexagonal flakes in nanoscale with numerous active sites having hydrophilic nature insist us to choose it as an electrocatalyst resulting in enhanced charge transfer mechanism. The binder free NiSe2/CC exhibits superior catalytic activity employing overpotential of −111 mV and 210 mV in HER and OER to draw 10 mA/cm2 current density, respectively in 1M KOH solution. Sustainability of electrocatalyst is also investigated in extreme pH. Thus, the water splitting device which consists of NiSe2/CC electrodes as cathode and anode in 1M KOH electrolyte, requires only 1.47 V to achieve 10 mA/cm2 current density.