Enhanced Electrocatalytic Performance through Body Enrichment of Co-Based Bimetallic Nanoparticles In Situ Embedded Porous N-Doped Carbon Spheres
Enhanced Electrocatalytic Performance through Body Enrichment of Co-Based Bimetallic Nanoparticles In Situ Embedded Porous N-Doped Carbon Spheres
复制标题
通过原位嵌入多孔氮掺杂碳球体富集钴基双金属纳米颗粒增强电催化性能
作者：
Song Qianqian;Li Junqi;Wang Shaolan;Liu Junli;Liu Xiaoxu;Pang Lingyan;Li Hu;Liu Hui
扩展负载活性物质的可用体空间并可控地定制d带中心以使其符合催化剂的费米能级是至关重要的，但对于增强电催化性能来说极具挑战性。本文提出了一种三聚氰胺桥联的自构建策略，将Co基纳米颗粒原位嵌入N掺杂多孔碳球（CoM-e-PNC）中，并通过Co与另一种过渡金属M（M = Ni，Fe，Mn，Cu）的合金化实现d带中心位置的可控剪裁。多孔碳球体内活性位点的富集和暴露，以及通过优化d带中心位置诱导的OH物质吸附和O2解吸之间的最佳平衡，共同增强了析氧反应（OER）性能。同时，d带中心位置与OER活性的关系符合火山曲线规律，其中CoNi‐e‐PNC催化剂在碱性介质中的OER活性最高，在10 mA cm− 2时的过电位为0.24 V，优于以往报道的CoNi基催化剂。此外，CoNi-e-PNC催化剂还表现出高OER稳定性，100 h后电流略有下降。
Extending available body space loading active species and controllably tailoring the d‐band center to Fermi level of catalysts are of paramount importance but extremely challenging for the enhancement of electrocatalytic performance. Herein, a melamine‐bridged self‐construction strategy is proposed to in situ embed Co‐based bimetallic nanoparticles in the body of N‐doped porous carbon spheres (CoM‐e‐PNC), and achieve the controllable tailoring of the d‐band center position by alloying of Co and another transition metal M (M = Ni, Fe, Mn, and Cu). The enrichment and exposure of the active sites in the body interior of porous carbon spheres, and the best balance between the adsorption of OH species and the desorption of O2induced by optimizing the d‐band center position, collectively enhance the oxygen evolution reaction (OER) performance. Meanwhile, the relationship of d‐band center position and OER activity is found to exhibit the volcano curve rule, where the CoNi‐e‐PNC catalyst shows optimal OER performance with an overpotential of 0.24 V at 10 mA cm−2in alkaline media, outperforming those of the ever‐reported CoNi‐based catalysts. Besides, CoNi‐e‐PNC catalyst also demonstrates high OER stability with slight current decrease after 100 h.