Abstract
Advanced electrocatalysts for the fabrication of sustainable hydrogen from water splitting are innermost to energy research. Herein, we report the growth of iron diselenide (FeSe2) nanorods on graphene oxide (GO) sheets using two-step process viz., simple hydrothermal reduction and followed by wet chemical process. The orthorhombic phase of FeSe2 incorporated GO nanosheet was developed as a low-cost and efficient electrocatalyst for hydrogen evolution reaction (HER) by water splitting. The phase purity, crystalline structure, surface morphology and elemental composition of the synthesized samples have been investigated by UV–visible absorption spectroscopy (UV–vis), fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray analysis (EDS). Voltammetry and Tafel polarization methods have been utilized to assess the performance of various weight ratio of GO nanosheet in FeSe2 nanorods towards H2 evolution. Detailed electrochemical investigations revealed that the 30% FeSe2/GO composite showed a tremendous electrocatalytic HER activity in acidic medium with high cathodic current density of 9.68 mA/cm2 at η = 250 mV overpotential and with a Tafel slope of 64 mV/dec. The 30% FeSe2/GO composite offers a high synergistic effect towards HER activity, which is mainly due to high electrochemical active catalytic sites, low charge-transfer resistance and enhanced electrocatalytic performances of H2 production. The present analysis revealed the possible application of FeSe2/GO composite as a promising low-cost alternative to platinum based electrocatalysts for H2 production.
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•Growth of FeSe2 nanorods on GO nanosheets was achieved via a two-step approach.•Hydrothermal reduction and wet chemical process have been employed.•FeSe2/GO composites were utilized as low-cost Pt-free electrocatalyts for HER.•Among various composites, 30% FeSe2/GO offered a synergistic effect towards HER.•GO in FeSe2 may be an efficient in conducting constituent of the electrocatalyst.