Vanadium redox flow batteries (VRFBs) are safe and promising in large-scale energy storage but are restricted by tardy redox reaction rates of carbon felt (CF) electrodes. Biomass carbon has the potential to overcome the challenges due to adjustable pore structure, heteroatom doping, and economic benefits. Herein, a bamboo-derived carbon-modified CF with O, N codoping and hierarchical porous (ABC-N-CF) was fabricated via selective removal of hemicelluloses and lignin and plasma post-treatment. The hierarchical porous structure of biomass carbon is conducive to an increase in edge defects and electrolyte infiltration. The optimal O, N codoped configuration was analyzed by density functional theory, revealing the reason for the carboxyl ortho-graphitic nitrogen codoped biomass carbon achieving rapid charge migration for the VO²⁺/VO₂⁺ redox couples. Furthermore, a single battery assembled with ABC-N-CF remained only with a 0.01 Ω·h^–1 variation of R_ct at 120 mA·cm^–2 over 1000 cycles. We believe that this study not only provides a promising strategy for high-performance biomass carbon-modified electrodes in VRFBs but also offers an effective method of realizing biomass conversion into energy storage materials for sustainable utilization.

中文翻译：

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用于钒氧化还原液流电池的富杂原子分级多孔生物质碳


全钒氧化还原液流电池（VRFB）在大规模储能方面是安全且有前景的，但受到碳毡（CF）电极迟缓的氧化还原反应速率的限制。生物质碳由于可调节的孔隙结构、杂原子掺杂和经济效益而具有克服这些挑战的潜力。在此，通过选择性去除半纤维素和木质素以及等离子体后处理，制备了具有O、N共掺杂和分级多孔的竹源碳改性CF（ABC-N-CF）。生物质碳的分级多孔结构有利于边缘缺陷和电解质渗透的增加。采用密度泛函理论分析了O、N共掺杂的最佳构型，揭示了羧基正石墨氮共掺杂生物质碳实现VO ²⁺ /VO ₂ 快速电荷迁移的原因 ⁺ 氧化还原对。此外，用 ABC-N-CF 组装的单个电池在 120 mA·cm ^–2 下仅保持 0.01 Ω·h ^–1 的 R _ct 变化。 1000 次循环。我们相信，这项研究不仅为 VRFB 中的高性能生物质碳改性电极提供了一种有前途的策略，而且还提供了一种实现生物质转化为可持续利用的储能材料的有效方法。