Design Strategies of Non‐Noble Metal‐Based Electrocatalysts for Two‐Electron Oxygen Reduction to Hydrogen Peroxide

Abstract

Hydrogen peroxide (H2O2) is a highly value‐added and environmentally friendly chemical with various applications. The production of H2O2 by electrocatalytic 2e− oxygen reduction reaction (ORR) has drawn considerable research attention, with a view to replacing the currently established anthraquinone process. Electrocatalysts with low cost, high activity, high selectivity, and superior stability are in high demand to realize precise control over electrochemical H2O2 synthesis by 2e− ORR and the feasible commercialization of this system. This Review introduces a comprehensive overview of non‐noble metal‐based catalysts for electrochemical oxygen reduction to afford H2O2, providing an insight into catalyst design and corresponding reaction mechanisms. It starts with an in‐depth discussion on the origins of 2e−/4e− selectivity towards ORR for catalysts. Recent advances in design strategies for non‐noble metal‐based catalysts, including carbon nanomaterials and transition metal‐based materials, for electrochemical oxygen reduction to H2O2 are then discussed, with an emphasis on the effects of electronic structure, nanostructure, and surface properties on catalytic performance. Finally, future challenges and opportunities are proposed for the further development of H2O2 electrogeneration through 2e− ORR, from the standpoints of mechanistic studies and practical application.

Synergistic Electronic and Pore Structure Modulation in Open Carbon Nanocages Enabling Efficient Electrocatalytic Production of H2O2 in Acidic Medium

“…[1a-c] Currently, the major way to generate H 2 O 2 relies on energy and waste intensive electronic structure will enable optimized binding of intermediates on the catalytic surfaces. [11] Heteroatom doping and introduction of OFGs and defects are desirable strategies to improve the electrocatalytic performance of carbon-based electrocatalysts. [12a-d] For example, oxygen atom was doped into the carbon lattice by Kim et al to modulate the electronic structure of adjacent carbon atom, thus enhancing the catalytic activity of the carbon atom near the epoxy group and ring ether defects for H 2 O 2 production.…”

“…[ 10a–d ] The well‐tuned electronic structure will enable optimized binding of intermediates on the catalytic surfaces. [ 11 ] Heteroatom doping and introduction of OFGs and defects are desirable strategies to improve the electrocatalytic performance of carbon‐based electrocatalysts. [ 12a–d ] For example, oxygen atom was doped into the carbon lattice by Kim et al.…”

Oxygenated P/N co-doped carbon for efficient 2e−oxygen reduction to H2O2

“…The majority of sites bind OOH* weakly, resulting in step (1) being the rate-determining step (RDS). 68 Sites 11 and 12 have relatively lower energy barriers, corresponding to 0.02 eV and 0.13 eV, respectively (Fig. 5B).…”

Composition Engineering of Amorphous Nickel Boride Nanoarchitectures Enabling Highly Efficient Electrosynthesis of Hydrogen Peroxide

“…Recently, several kinds of inexpensive transition metalbased compounds including oxides, [15][16][17] chalcogenides, [18][19][20] and phosphides [21][22][23] have been exploited for selective reduction of O 2 to H 2 O 2 , by which their huge potential as 2e − ORR electrocatalysts has been eloquently confirmed. For instance, in 2021, Jiang et al found that the Cu 7.2 Se 4 delivered the 2e − selectivity as high as 90%, [18] and following this observation, Zhao et al in 2022 reported that the 2e − selectivity for Ni 2−x P could be reached higher than 92%.…”