Constructing sulfur and oxygen super-coordinated main-group electrocatalysts for selective and cumulative H 2 O 2 production.

Direct electrosynthesis of hydrogen peroxide (H ₂ O ₂ ) via the two-electron oxygen reduction reaction presents a burgeoning alternative to the conventional energy-intensive anthraquinone process for on-site applications. Nevertheless, its adoption is currently hindered by inferior H ₂ O ₂ selectivity and diminished H ₂ O ₂ yield induced by consecutive H ₂ O ₂ reduction or Fenton reactions. Herein, guided by theoretical calculations, we endeavor to overcome this challenge by activating a main-group Pb single-atom catalyst via a local micro-environment engineering strategy employing a sulfur and oxygen super-coordinated structure. The main-group catalyst, synthesized using a carbon dot-assisted pyrolysis technique, displays an industrial current density reaching 400 mA cm ^-2 and elevated accumulated H ₂ O ₂ concentrations (1358 mM) with remarkable Faradaic efficiencies. Both experimental results and theoretical simulations elucidate that S and O super-coordination directs a fraction of electrons from the main-group Pb sites to the coordinated oxygen atoms, consequently optimizing the *OOH binding energy and augmenting the 2e ^- oxygen reduction activity. This work unveils novel avenues for mitigating the production-depletion challenge in H ₂ O ₂ electrosynthesis through the rational design of main-group catalysts.
(© 2024. The Author(s).)