Self-Supported MoO<sub>2</sub>/MoSi<sub>2</sub> Ceramic Electrode for High Current Density Hydrogen Evolution Reaction
Nianwang Ke, Haisen Huang, Feihong Wang, Anding Huang, Chuntian Tan, Binbin Dong, Yutong Wu, Luyuan Hao, Xin Xu, Simeon Agathopoulos
Abstract
Ceramic electrodes are cost-effective and stable at high current densities. Thus, they are highly considered for industrial hydrogen production. In this study, a novel self-supported MoO 2 /MoSi 2 ceramic electrode, with open finger-like holes and excellent electrochemical performance, was successfully prepared by phase-inversion, the shaping method of tape-casting, and hydrothermal treatment. The obtained MoO 2 /MoSi 2 electrode has a lower overpotential than the Pt/C electrode at current densities greater than 330 and 410 mA cm –2 in an alkaline and acidic environment, respectively. Furthermore, the electrode exhibits excellent stability at 10–1000 mA cm –2 for 260 h in both alkaline and acidic solutions. Density functional theory calculations showed that the MoO 2 /MoSi 2 heterostructure displays the lowest H adsorption free energy and the highest density of states around the Fermi level.