Efficient Neutral H 2 O 2 Electrosynthesis from Favorable Reaction Microenvironments via Porous Carbon Carrier Engineering.

The efficient electrosynthesis of hydrogen peroxide (H 2 O 2 ) via two-electron oxygen reduction reaction (2e - ORR) in neutral media is undoubtedly a practical route, but the limited comprehension of electrocatalysts has hindered the system advancement. Herein, we present the design of model catalysts comprising mesoporous carbon spheres-supported Pd nanoparticles for H 2 O 2 electrosynthesis at near-zero overpotential with approximately 95 % selectivity in a neutral electrolyte. Impressively, the optimized Pd/MCS-8 electrocatalyst in a flow cell device achieves an exceptional H 2 O 2 yield of 15.77 mol g catalyst -1  h -1 , generating a neutral H 2 O 2 solution with an accumulated concentration of 6.43 wt %, a level sufficiently high for medical disinfection. Finite element simulation and experimental results suggest that mesoporous carbon carriers promote O 2 enrichment and localized pH elevation, establishing a favorable microenvironment for 2e - ORR in neutral media. Density functional theory calculations reveal that the robust interaction between Pd nanoparticles and the carbon carriers optimized the adsorption of OOH* at the carbon edge, ensuring high active 2e - process. These findings offer new insights into carbon-loaded electrocatalysts for efficient 2e - ORR in neutral media, emphasizing the role of carrier engineering in constructing favorable microenvironments and synergizing active sites.