# Scalable and Customizable Single‐Atom Coatings for pH‐Universal H2O2 Electrosynthesis

## TL;DR

A new method creates scalable single-atom catalyst coatings for efficient hydrogen peroxide production in various electrode shapes.

## Contribution

A universal one-step soot-deposition route for fabricating SAC-coated electrodes with multiscale control.

## Key findings

- Pd-SAC-GDE achieves pH-universal H2O2 production at 500 mA cm−2 for 100 hours.
- A curvature-enhanced electric field promotes O2 activation at Pd-O3 sites for selective H2O2 production.

## Abstract

Achieving scalable fabrication of robust and uniform single‐atom catalyst‐based gas‐diffusion electrodes (SAC‐GDEs) remains challenging. Here, a universal one‐step soot‐deposition route was developed to convert various metal‐containing paraffins into conformal single‐atom catalyst (SAC) coatings on diverse electrodes (1D fibers, 2D plates, and 3D foams). The process provides multiscale control, from precursor‐defined molecular coordination to micropore wettability and macroscopic geometry, to collectively engineer hierarchical coating films that couple intensified mass transfer and high intrinsic catalytic activity for efficient H2O2 electrosynthesis. As a device‐level demonstration, Pd‐SAC‐GDE delivers pH‐universal H2O2 production under an industrial‐level current (500 mA cm−2) for 100 h, achieving a record‐high H2O2 yield of 16.9 mol g−1 h−1. A tip‐enhanced mechanism was proposed based on constant‐potential calculations. The results reveal that the curvature‐enhanced localized electric field promotes O2 polarization and activation at the Pd‐O3 sites, thereby facilitating both *OOH generation and adsorption and ultimately leading to highly selective H2O2 production. This facile, broadly applicable fabrication strategy significantly advances the scalable manufacture of SAC‐coated GDEs for environmental and sustainable catalysis.

A universal one‐step soot‐deposition route was developed to convert various metal‐containing paraffins into conformal single‐atom catalyst (SAC) coatings on diverse electrodes, yielding robust, efficient SAC‐coated gas diffusion electrodes for H2O2 electrosynthesis.