CNT-modified globugraphite carbon foam for hydrogen peroxide generation: structural and electrochemical characterisation

Three-dimensional (3D) porous carbon architectures offer unique advantages for electrochemical processes due to their high surface area, interconnected porosity, and intrinsic conductivity. In this study, a carbon nanotube-modified Globugraphite composite (CNT-GG) is developed to achieve efficient electrogeneration of hydrogen peroxide (H₂O₂). The composite exhibits exceptionally high porosity (98%), ultralow density (0.04–0.05 g·cm−3), and a hierarchical porous structure, providing enhanced active surface exposure and mass transport. Incorporation of carbon nanotubes (CNTs), consistent with a multi-walled structure, within the GG matrix modifies the pore architecture and promotes a more interconnected network enhancing mass transport and charge-transfer processes, thereby improving electrochemical activity. It significantly improves effective bulk conductivity (up to 662 S/m), mechanical strength as determined by higher flexural and modulus values, and slight enhancement in thermal stability. The optimized CNT-GG structure also exhibits reduced tortuosity (from 4.29 to 1.21), facilitating efficient charge-transfer pathways. Electrochemical evaluation demonstrates that CNT-GG electrodes markedly enhance the in-situ generation of H₂O₂, reaching concentrations up to 48 μmol·L−1 within 30 min while achieving a high specific H₂O₂ productivity of 2.64 μmol·cm−2·min−1. These results demonstrate that CNT modification synergistically improves porosity, conductivity, defect-rich carbon structure contributing to electrochemical activity, positioning CNT-GG as a promising electrode material for H₂O₂ electrogenaration systems.