Promoting Oxygen Electrochemical Reduction to Hydrogen Peroxide through Fabricating Hierarchical Pores

In this work, we demonstrate an effective approach to enhance the activity and selectivity of carbon materials for hydrogen peroxide （H2O2）production by means of interface engineering. Carbon black and/or graphite are mixed with polytetrafluoroethylene（PTFE）and pore-forming agent to form a gas diffusion electrode for H2O2. Structural characterizations find that PTFE not only acts as a binder, it also changes the original pore size distribution of carbon materials by increasing the number of mesoporous and micron pores. These unique hierarchical pores enhance an efficient gas transmission and dispersion network system. Meanwhile, a number of polymer phases are generated in the inner of electrode with the size of 30nm-1μm, which enhance the affinity of catalyst surface to oxygen. Under the detachable H-type H2O2 test device and optimized conditions, H2O2 concentration can reach 11.8wt%. The simple physical mixing engineering fabricating hierarchical pores would be helpful to other electrochemical processes involving gas-solid-liquid three-phase interface.