Single atomic Ru in TiO 2 boost efficient electrocatalytic water oxidation to hydrogen peroxide.

Electrocatalytic two-electron water oxidation affords a promising approach for distributed production of HO using electricity. However, it suffers from the trade-off between the selectivity and high production rate of HO due to the lack of suitable electrocatalysts. In this study, single atoms of Ru were controllably introduced into titanium dioxide to produce HO through an electrocatalytic two-electron water oxidation reaction. The adsorption energy values of OH intermediates could be tuned by introducing Ru single atoms, offering superior HO production under high current density. Notably, a Faradaic efficiency of 62.8% with an HO production rate of 24.2 μmol min cm (>400 ppm within 10 min) was achieved at a current density of 120 mA cm. Consequently, herein, the possibility of high-yield HO production under high current density was demonstrated and the importance of regulating intermediate adsorption during electrocatalysis was evidenced.