Accelerating Proton Transfer via Tetrahydroxy-1,4-Benzoquinone Intercalation for Enhanced Oxygen Evolution Reaction

The slow hydrogen proton transfer rate during the oxygen evolution reaction (OER) process results in sluggish kinetics of proton desorption and local acid corrosion of active sites, which significantly impairs catalytic activity and stability, especially at high current density. In this work, an expedited proton removal has been realized using tetrahydroxy-1,4-benzoquinone (THQ) as a proton transfer relay. THQ-inserted NiFeOOH (NiFeOOH/THQ) through a sample one-step hydrothermal method. THQ not only effectively reduces the electron cloud density around Ni/Fe active sites as a strong electron-withdrawing ligand, but also connects the catalyst/electrolyte interface hydrogen bond to accelerate proton transfer enriched on the catalytic surface. NiFeOOH/THQ exhibited enhanced OER activity, with an overpotential of only 260 mV at 100 mA cm^-2, which is considerably lower than that of NiFeOOH (320 mV). The Tafel slope measured 22.98 mV dec^-1, indicating the accelerated OER kinetics. Furthermore, NiFeOOH/THQ can maintain stable operation at 100 mA cm^-2 for 250 h. This improved OER performance is attributed to the formation and robustness of highly active Ni³⁺ sites and mitigated local acid corrosion stemming from regulated electron/proton transfer. This study presents a novel design strategy for advanced electrocatalysts by facilitating rapid proton neutralization and stabilizing active sites through ligand intercalation.