Enhanced catalytic activity of Ru through N modification toward alkaline hydrogen electrocatalysis

Exploring highly efficient electrocatalysts and understanding the reaction mechanisms for hydrogen electrocatalysis, including hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) in alkaline media are conducive to the conversion of hydrogen energy. Herein, we reported a new strategy to boost the HER/HOR performances of ruthenium (Ru) nanoparticles through nitrogen (N) modification. The obtained N-Ru/C exhibit remarkable catalytic performance, with normalized HOR exchange current density and mass activity of 0.56 mA/cm(2) and 0.54 mA/mu g, respectively, about 4 and 4.5 times higher than those of Ru/C, and even twofold enhancement compared to commercial Pt/C. Moreover, at the over-potential of 50 mV, the normalized HER current density of N-Ru/C is 5.5 times higher than that of Ru/C. Experimental and density functional theory (DFT) results verify the electronic regulation of Ru after N incorporation, resulting in the optimized hydrogen adsorption Gibbs free energy (Delta G(H*)) and hence enhancing the HOR/HER performance. (C) 2021 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Automated summary

This study presents a new strategy to enhance the electrocatalytic performance of ruthenium nanoparticles for hydrogen oxidation and hydrogen evolution reactions in alkaline media through nitrogen modification. The nitrogen-modified ruthenium nanoparticles exhibit remarkable catalytic performance, outperforming both the untreated ruthenium nanoparticles and commercial platinum catalysts. The enhanced performance is attributed to the electronic regulation of ruthenium after nitrogen incorporation, optimizing the hydrogen adsorption Gibbs free energy.