3D Structured Au(NiMo)/Ti Catalysts for Hydrogen Evolution Reaction

Abstract

Hydrogen generation via water splitting in alkaline media is the most promising, alternative, clean, and next-generation technology that can fulfill the future energy demands and overcome the challenge of global warming. The kinetics of hydrogen generation via water splitting through electrochemical process mainly rely on hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Material selection and material design are the keys to developing highly active, low-cost, and stable non-noble metal electrocatalysts but also are of great challenge.The Au(NiMo)/Ti-based catalysts were prepared via chemical and electrochemical methods in this study. Initially, the NiMo coatings on the Ti surface (1x1cm) were electrodeposited from a bath containing 0.01 M Na2MoO4 and 0.01, 0.1, and 0.5 M NiSO4 in an acidic condition. The process of electrochemical deposition was carried out at the current of 0.1 mA and 1 mAfor 3 min. The gold nanoparticles were deposited on the previously prepared NiMo/Ti electrodes by galvanic displacement through their immersion into an acidic Au-containing solution for 10s. The morphology and composition of the newly prepared catalysts have been investigated via SEM, XRD, EDS, and ICP-OES. The investigation of electrocatalytic properties of the prepared catalysts was performed by recording linear sweep voltammograms in 1M NaOH solution at a potential scan rate of 10 mVs-1 at 25-75⁰C temperature range.It was observed that the power densities for the newly prepared Au(NiMo)/Ti catalysts with the Au loading from 2 up to 4 µgAucm-2 were 1.3 to 1.8 times higher than using NiMo/Ti catalysts for HER. Acknowledgment This project has received funding from European Social Fund (project No 09.3.3-LMT-K-712-19-0138) under a grant agreement with the Research Council of Lithuania (LMTLT).