Controllable Modification of NiMo-Based Electrocatalysts for Water Splitting in Alkaline Solution

Abstract

Pt modified NiMo-based nanomaterials with stable morphology and structure were prepared by simple and rapid operation. The introduction of small amounts of Pt can not only improve the adsorption and desorption of oxygen intermediates due to the accompanying defects, but also improve the conductivity and promote charge transfer. The synergistic effect of Pt and NiMo-based substance can make the nanomaterials give full play to the advantages of each component, and the catalyst shows good performance in alkaline solution by adjusting the amount of Pt introduced.Under the current density of 10 mA cm- 2, the overpotential of 102 mV is required for hydrogen evolution reaction. And 399 mV is required for oxygen evolution reaction to generate 50 mA cm- 2. In addition, the effects of direct hydrothermal method and immersion method about introduction of Pt on properties of the materials were explored. It is worth noting that the immersion method is simpler and more effective. When used in a two-electrode system, it only needs a voltage of 1.58 V to achieve current densities of 10 mA cm- 2. What’s more, the nanomaterial shows excellent stability up to 45 hours without obvious decrease of current density, which makes it hopeful to be applied in practice and become a strong competitor of bifunctional electrocatalyst.