High-efficient removal of oxygen (O2) impurity from hydrogen (H2) flow on nickel-based oxide: effect of metal dopants

Abstract

Hydrogen is considered as a green energy source, which has attracted widespread attention. Electrocatalytic hydrogen production is a promising technology for generating clean hydrogen. However, the by-product oxygen in this process would lead to a risk of explosion that should be removed before using. In this work, nickel-based oxides doped with variable proportions of Mn, Co, and Cu were used for oxygen removal through catalytic oxidation technology. The catalytic test results show that the optimized catalysts, including 4NiMn, 2Ni1.5Co, and NiCu exhibit better performance. Among all the catalysts, 4NiMn catalyst has the best catalytic performance, achieving a 90% oxygen removal rate below 100 °C. According to the results of H2-TPR, O2-TPD and H2-TPD, the catalysts with better deoxidation effect (4NiMn, 2Ni1.5Co and NiCu) exhibit a stronger oxidation-reduction ability. 4NiMn has higher amounts of adsorption surface oxygen species and overflow hydrogen, which are key factors of the promoting deoxidation effect. Overall, it can be concluded that the optimal catalytic performance of 4NiMn can be attributed to its ability to better adsorb oxygen on its surface, promote the release of overflow hydrogen and participate in oxidation-reduction reactions.