Recently, electrocatalyst with high reactivity and stability towards HER are necessary for hydrogen generation. Herein, graphene oxide supported MnO2-TiO2 nanourchins synthesized by thermal decomposition technique was incorporated to bimetallic phosphide Ni-Co-P coatings by electroless plating technique. Transition metal mixed oxides on graphene oxide support can impart a greater influence on electrocatalytic hydrogen evolution. The detailed studies regarding the enhanced surface morphology and electronic environment of the electrocatalyst were achieved by scanning electron microscopy coupled with elemental distribution analysis (SEM-EDS), High resolution tunnelling electron microscopy (HRTEM), X-ray diffraction (XRD) and spectral (UV, IR) analysis. The superior electrochemical activity of modified electrode have been further confirmed by Linear sweep voltammetry (LSV), Tafel polarization studies, electrochemical impedance spectroscopy (EIS), Cyclic voltammetry (CV), Open circuit potential (OCP) and Chronoamperometry techniques. During hydrogen evolution, the incorporation of composite onto bimetallic phosphide cause a drastic decreases in overpotential value to 190 mVdec-1 with a lower Tafel slope of 45 mvdec-1 as compare to pure Ni-Co-P and Ni-P plate in 1 M NaOH and the studies reveals that the modified electrode follows Volmer-Heyrovsky mechanism. The lower Rct of 140.8 Ω obtained from Nyquist plot of modified electrodes ensures the fastest electron transfer kinetics and confirms its more facile electrocatalytic nature towards hydrogen evolution. The modified electrodes was durable, long term stable, economically viable and performance was consistent over a wide span of time during alkaline hydrogen evolution reaction. The enhanced performance of modified electrode can be ascribed to the intermetallic synergetic effect arises within Ni-Co-P matrix and MnO2-TiO2 nanourchins. These conclusions lead innovative insights on future perspective for the development and tuning of novel electrocatalysts with enhanced electrochemical performance for hydrogen evolution reaction.

Graphene supported manganous mixed oxide nanourchins as high performance hydrogen evolution electrodes in basic media

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.