Electrochemical hydrogen evolution catalyzed by SrMoO_4 spindle particles in acid water

摘要

In this work, SrMoO_4 spindle particles have been examined as hydrogen evolving elec-trocatalysts for the first time in acid water electrolytes. Strontium molybdate spindle particles were prepared by conventional hydrothermal method. The products obtained were characterized by X ray diffraction (XRD) and Transmission electron microscopy (TEM). The electrochemical hydrogen evolution reaction (HER) studies were performed on these particles using H_2SO_4 solutions with two different concentrations, namely, 0.5 M and 2.5 M. The HER activity of SrMoO_4 samples have been compared with that of α-MoO_3. An increased rate of hydrogen evolution was observed for SrMoO_4. It has also been noticed that the HER overpotential decreased and the current density increased when the SrMoO_4 electrodes were subjected to continuous scan cycling in the acid electrolytes. Electrochemical Impedance Spectroscopic (EIS) studies indicated that the lesser preparative reaction time of SrMoO_4 resulted in decrease in the HER charge transfer resistance.