Atomic-level functionalized carbon-based materials for effective electrosynthesis of hydrogen peroxide: A review

Hydrogen peroxide (H2O2) is in great demand in disinfection, bleaching, wastewater treatment and other fields. However, the traditional preparation of anthraquinone is complicated and uneconomical. Electrocatalytic two-electron oxygen reduction reaction to produce H2O2 (2e- ORR) as a green way has attracted wide attention. The key to this reaction is to design the catalysts with excellent catalytic performance. Carbon-based materials with good conductivity, mass transfer, cheap economy, adjustable surface and structure, have been considered as catalysts with good potential to solve the problem of preparing large quantities of H2O2. Currently, atomic functionalized carbon-based materials can be divided into two main design strategies, one of which is introducing doping atoms, such as N, B and O-groups, into pure carbon materials and the other is to design single metal atoms, including d/p-block metal elements, anchored to carbon materials. Both functional carbon materials modified by different atoms have good application potential in 2e- ORR. In this paper, we start by reviewing the relevant reports of the above two types of atomic functionalized carbon-based materials for the first time. Second, we compare the performance of the above two types of atomic functionalized carbon-based materials with respect to 2e- ORR and find that they both have high H2O2 selectivity, but the latter is generally superior to the former one in the aspect of H2O2 yield. Finally, the current research situation and the future design directions of atomic functionalized carbon-based materials for 2e- ORR are both summarized.