Fig. 5: Mechanistic investigation of the Ni0.67V0.33-LDH/ACT-mediated EAO.

Comparison of a Bode plots and b Nyquist plots at 1.37 V vs. RHE for Ni0.67V0.33-LDH, Ni0.67V0.33-LDH + BA, Ni0.67V0.33-LDH/ACT, and Ni0.67V0.33-LDH/ACT + BA. In situ Raman spectra (without iR compensation) of c β-Ni(OH)2, d Ni0.67V0.33-LDH, e Ni0.67V0.33-LDH with ACT, and f Ni0.67V0.33-LDH with ACT and BA at various constant potentials (increased from 1.27 to 1.77 V vs. RHE). g Charge density difference of ACTH adsorption for the corresponding structures of V-NiOOH at Ni active site. Cyan and yellow represent the depletion and accumulation of electrons, respectively. h Electron localization function (ELF) for the structure of ACTH adsorption on the V-NiOOH surface. The dark blue regions represent localized electron distribution, the red regions represent electronic delocalized distribution. Electrons localized in the range of 0.0–1.0. i Proposed a mechanism for the Ni0.67V0.33-LDH/ACT-mediated EAO. The color for each element is light gray for V, pale blue for Ni, red for O, dark gray for C, blue for N, and white for H.