CO2 Laser-Induced Graphene with an Appropriate Oxygen Species as an Efficient Electrocatalyst for Hydrogen Peroxide Synthesis

Oxygen species functionalized graphene (O-G) is an effective electrocatalyst for electrochemically synthesizing hydrogen peroxide (H2O2) by a 2 e(-) oxygen reduction reaction (ORR). The type of oxygen species and degree of carbon crystallinity in O-G are two key factors for the high catalytic performance of the 2 e(-) ORR. However, the general preparing method of O-G by the precursor of graphite has the disadvantages of consuming massive strong oxidant and washing water. Herein, the biomass-based graphene with tunable oxygen species is rapidly fabricated by a CO2 laser. In a flow cell setup, the laser-induced graphene (LIG) with abundant active oxygen species and graphene structure shows high catalytic performance including high Faraday efficiency (over 78 %) and high mass activity (814 mmolg(catalyst)(-1) h(-1)), superior to most of the reported carbon-based electrocatalysts. Density function theory demonstrates the meta-C atoms at nearby C-O, O-C=O species are the key catalytic sites. Therefore, we develop one facile method to rapidly convert biomass to graphene electrocatalyst used for H2O2 synthesis.

Automated summary

Oxygen species functionalized graphene is an effective electrocatalyst for synthesizing hydrogen peroxide through a two-electron oxygen reduction reaction. The type of oxygen species and carbon crystallinity are key factors for its high catalytic performance. However, the traditional method of preparing oxygen species functionalized graphene has drawbacks such as consuming a large amount of strong oxidant and requiring washing. In this study, biomass-based graphene with tunable oxygen species is rapidly fabricated using a CO2 laser and shows high catalytic performance in hydrogen peroxide synthesis.