M-N/C单原子催化剂电子结构-孔道分配双调控机制促进高效电催化二电子氧还原反应合成H2O2

鉴于传统蒽醌法制取H2O2存在能耗大、环境不友好等缺点，电催化二电子氧还原反应（2e-ORR）被认为是最具发展前景的一种H2O2合成途径。作为高效电催化剂代表，碳基材料在酸性介质中催化2e-ORR依然存在动力学不足、活性位密度低和H2O2滞留孔道易发生进一步还原导致产率低等瓶颈。本项目拟聚焦静电纺丝基3D单原子 M-N/C（M= Co, Mn等）纳米纤维催化剂，创新发展电位控制阳极化可控接枝方法，通过调控阳极化电极电位及溶液质子浓度实现催化剂选择性含O物种功能化，研究含O基团电子效应对活性中心电荷分布、M-OOH结合能的调控规律，阐明2e-ORR催化性能的增强机理；提出“微-介”双模板孔道分配均衡控制策略，促进3D电催化剂活性中心高度暴露、H2O2快速传导，从而兼顾高活性位密度和高H2O2产率；开发基于自支撑3D网络电极O2直接进料电合成H2O2电解池，实现安培级电流密度，助推实用化进程

In view of the high energy consumption and environment-unfriendly in the synthesis of hydrogen peroxide (H2O2) by the traditional anthraquinone method, electrocatalytic two-electrons oxygen reduction reaction (2e-ORR) is considered as an ideal approach to directly produce H2O2. Currently, as a representative of the efficient electrocatalyst, carbon-based materials still suffer from the sluggish catalytic kinetics in acidic solution, low active-site density and unsatisfactory H2O2 productivity resulted from the continuous reduction of H2O2 molecular trapped in the carbon-channel. To this end, this proposal will focus on the 3D single transition metal atom and N co-doped electrospun carbon nanofiber catalyst (SAM-N/CNF) and innovatively develop the potential-controlled anodization grafting method to achieve the functionalization of the selective O-containing species on the SAM-N/CNF catalyst through the precise adjustment of anodizing potentials and proton concentration of electrolyte. The regulation of the electronic effect for different O-containing groups on the charge-distribution of active center and M-OOH binding energy will be investigated to elucidate the enhancement mechanism of 2e-ORR. Moreover, the proposal will develop a balanced control strategy of “micro-mesopore” dual-template pore-distribution to promote the high exposure of active-sites and rapid H2O2 transfer, hence obtain the 3D electrocatalyst with high active-site density together with the enhanced H2O2 productivity. In the end, this proposal will design a novel electrosynthesis-cell based on the free-standing 3D network cathode to achieve the amperage-level current density, boosting the practical process of H2O2 electrosynthesis.