Highly Selective Oxygen Electroreduction to Hydrogen Peroxide on Sulfur‐Doped Mesoporous Carbon
Juan Du, Yicheng Liu, Ming Sun, Jing Guan, Aibing Chen, Buxing Han
Abstract
Abstract As a paradigm‐shifting material platform in energy catalysis, precisely engineered ordered mesoporous carbon spheres emerge as supreme metal‐free electrocatalysts, outperforming conventional carbon‐based counterparts through synergistic structural and electronic innovations. Herein, we architecturally design vertically aligned cylindrical mesoporous carbon spheres with atomic‐level sulfur doping (S‐mC) that establish unprecedented performance benchmarks in the two‐electron oxygen reduction reaction (2e − ‐ORR) to hydrogen peroxide. Systematic comparative studies reveal that the S‐mC catalysts achieve exceptional H 2 O 2 selectivity (>99%) and activity at current density of −3.5 mA cm −2 , surpassing state‐of‐the‐art metal‐free catalysts in current density. Impressively, the optimized S‐mC electrocatalyst in a flow cell device achieves an exceptional H 2 O 2 yield of 25 mol g catalyst −1 h −1 . The carbon matrix's unique sp 2 /sp 3 hybrid network coupled with S‐induced charge redistribution generates electron‐deficient hotspots that selectively stabilize *OOH intermediates, as evidenced by in situ spectroscopic characterization and DFT calculations. This structural–electronic synergy endows the carbon framework with metal‐like catalytic efficiency while maintaining inherent advantages of chemical robustness and cost‐effectiveness. The marriage of S‐doping engineering with mesoscopic pore architecture control opens a new way for developing efficient carbon‐based electrocatalysts for oxygen selective reduction to H 2 O 2 .