Noble-metal-free electrocatalysts toward H2O2 production

The exploration of high-efficiency, robust and low-cost electrocatalysts for hydrogen peroxide (H2O2) production receives increasing attention due to its key role in developing a new alternative to replace the traditional anthraquinone process. In recent years, significant achievements of non-noble metal electrocatalysts for H2O2 production have been made. Herein, this review presents recent advances of noble-metal-free electrocatalysts toward H2O2 production. Specifically, we first introduce the fundamental principle of on-site electrochemical synthesis of H2O2. Then, the classification and corresponding recent advances of noble-metal-free electrocatalysts are reviewed, including carbon-based materials (modified by pore structure adjustment, topology defects, heteroatom-doping and surface oxygen functionalization), metal compounds (e.g., NiO, MnO, FeO, Bi2Te3, and CoS2), metal single atom catalysts (e.g., Fe, Co, Ni, Mn, and Mo) and metal complexes. In parallel, the synthesis strategy, component, structure, electrochemical properties and reaction mechanism are highlighted. Finally, an outlook on current advances, challenges, and potential of noble-metal-free electrocatalysts towards H2O2 production is also discussed.