NSRRC Activity Report 2022

Energy Science 063 initial configuration during both HER and OER, without the formation of Ni/V/Ru oxides or Ni/V/Ru-derived species, indicating a structural transformation-free behavior. The researchers concluded that the synergistic effect between the atomic Ru site and Ni 3 V-LDH substrate resulted in the formation of a Ru–O– Ni bond that stabilized the oxygen- defect-rich surface and enabled the excellent performance and unique reconstruction-free property of the electrocatalyst. Fig. 3 : In situ XAS of Ru/Ni 3 V-LDH in an aqueous solution containing 1.0 M KOH during HER/OER. (a) Oxidation state of Ru/Ni in Ru/Ni 3 V-LDH and the corresponding HER current density versus control potentials. A.P.: as-prepared Ru/Ni 3 V-LDH. KOH: Ru/Ni 3 V-LDH soaked in the KOH electrolyte. (b) Fourier-transform EXAFS spectra at various bias voltages during HER. (c) Oxidation state of Ru/Ni in Ru/Ni 3 V-LDH and the corresponding OER current density versus control potentials. (d) Fourier-transform EXAFS spectra at various bias voltages during OER. [Reproduced from Ref. 2] Fig. 4 : In situ EXAFS fitting results and schematic models of Ru/Ni 3 V-LDH during HER/OER. (a) EXAFS fitting results of bond distances for Ru/Ni 3 V-LDH during HER. (b) EXAFS fitting results of coordination numbers for Ru/Ni 3 V-LDH during HER. (c) EXAFS fitting results of bond distances for Ru/Ni 3 V-LDH during OER. (d) EXAFS fitting results of coordination numbers for Ru/Ni 3 V-LDH during OER. [Reproduced from Ref. 2]