B–F Dual-Doped Carbon Nanotubes for Multi-Site and High-Rate Two-Electron Oxygen Reduction Reaction Electrocatalysis

Electrocatalytic two-electron oxygen reduction reaction (2e- -ORR) to produce hydrogen peroxide (H2O2) is a promising green way to replace the conventional anthraquinone reaction. Non-metallic catalysts are considered as low-cost catalysts due to their excellent stability and versatile surface chemistry. The performance of nonmetallic electrocatalysts is usually limited by the limited catalytic active sites on the surface. Here, we report fluorine and boron dual -doped carbon nanotubes (B-F-C) as a metal-free electrocatalyst for H2O2 production, fabricated via a fast microwave treatment. With the synergistic effect of F and B, this strategy can effectively convert carbon and boron atoms on carbon nanotubes into highly active sites. As a result, an H2O2 yield up to 24.3 mol g-1 L-1 is achieved over B-F-C with a stable selectivity of above 90% within 0.2-0.7 V vs. RHE in 0.1 M KOH. Density functional theory (DFT)calculations further confirm that the multiple active sites created by the dual doping of fluorine and boron are the key factor in improving the performance of 2e- -ORR electrocatalysis. Therefore, this work offers a promising prospect for the design and preparation of catalysts with high catalytic activity for H2O2 production and other catalytic areas of industrial significance.