Cheng-Peng's group from college of chemistry published the paper "Bixbyite-type Ln2O3 as promoters of metallic Ni for alkaline electrocatalytic hydrogen evolution" in Nature Communications. The paper revealed that the bixbyite-type lanthanide oxides can improve the catalytic activity and stability of metal nickel for alkaline hydrogen evolution reaction.

Figure 1 A series of Ni/Ln2O3 complex HER catalysts were designed and prepared by selective high temperature reduction method

This work develops a kind of promoters, the bixbyite-type lanthanide metal sesquioxides (Ln2O3), which can be implanted into metallic Ni by selective high-temperature reduction to achieve highly efficient Ni/Ln2O3 hybrid electrocatalysts toward hydrogen evolution reaction. The screened Ni/Yb2O3 catalyst shows the low overpotential (20.0 mV at 10 mA cm-2), low Tafel slope (44.6 mV dec-1), and excellent long-term durability (360 h at 500 mA cm-2), significantly outperforming the metallic Ni and benchmark Pt/C catalysts. The remarkable hydrogen evolution activity and stability of Ni/Yb2O3 are attributed to that the Yb2O3 promoter with high oxophilicity and thermodynamic stability can greatly enlarge the active-site density, reduce the energy barrier of water dissociation, optimize the free energy of hydrogen adsorption, and avoid the oxidation corrosion of Ni. More significantly, the ability of Ln2O3 to promote the water dissociation should not be limited to alkaline HER system, which will be also available to other catalytic reactions involving water dissociation, showing important research significance.

Tianjin Normal University is the first unit and the corresponding unit. Zhengzhou University of Light Industry is the joint communication unit. Lecturer Sun Hongming from College of Chemistry is the first author, and Professor Li Cheng-Peng and Professor Du Miao are the corresponding authors. This work was supported by the National Natural Science Foundation of China (52101268, H.-S.) and the Science & Technology Development Fund of Tianjin Education Commission for Higher Education (2019KJ088, H.-S.)

Paper links: https://doi.org/10.1038/s41467-022-31561-4