Abstract
The invention of sustainable electrocatalysts for electrochemical hydrogen evolution reaction (HER) as inexpensive and efficient contenders is very necessary to energy future of the day life replacing determinate conventional fuel. Ni based electrocatalysts are the most promising non-noble transition metals as an alternative to precious metals. Here, we electroplated new 3D-Ni-Co-TiO2 nanocomposites as the benchmark electrocatalyst for HER in alkaline electrolytes. Electrodeposited Nickel-cobalt-titania nanocomposites of various matrices compositions were obtained via a gluconate plating bath containing colloidal TiO2 particles. The surface morphology, chemical composition and crystal structure of the various 3D-Ni-Co-TiO2 nanocomposites were characterized by SEM, TEM, EDX, XPS and XRD analysis. Mixing of ultrasonication and mechanical stirring guarantees the homogenous dispersion of TiO2 inside Ni-Co matrices which confirmed by the TEM image. 3D-Ni-Co-TiO2 nanocrystalline composites exposed the electrocatalytic activity greater than the most active metal Pt. Ni-47.6Co-4.01TiO(2) nanocrystalline composite attained the highest current density for HER of 900 mA cm(-2) while Pt showed 630 mA cm(-2) at - 2 V potential in 1.0 M KOH. The nanocrystalline Ni-Co-TiO2 composites possess the superior electrocatalytic properties toward the HER in 1.0 M KOH which are remarkably active than the most known electrocatalyst Pt by 1.5 times. The electrocatalytic properties of 3D-Ni-Co-TiO2 composites toward the HER were studied utilizing potentiodynamic polarization and electrochemical impedance spectroscopy methods.