Cytosine-Co assemblies derived CoNx rich Co-NCNT as efficient trifunctional electrocatalyst
Cytosine-Co assemblies derived CoNx rich Co-NCNT as efficient trifunctional electrocatalyst
复制标题
胞嘧啶-Co组装衍生的富含CoNx的Co-NCNT作为高效三功能电催化剂
DOI：
10.1016/j.jcis.2020.11.095
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发表时间：
2021
影响因子：
9.9
通讯作者：
Qiu Shilun
中科院分区：
文献类型：
--
作者：
Wang Yu;Yu Honghao;Zhu Liangkui;Shi Zhiqiang;Wang Runwei;Zhang Zongtao;Qiu Shilun
碳-金属复合材料是一种很有前途的多功能电催化剂，但制备具有可调结构和强相互作用的碳-金属复合材料仍具有挑战性。在这里，我们提出了一个独特的气体发泡组装策略，制备胞嘧啶钴螯合衍生的钴和氮共掺杂碳纳米管（Co-NCNT）。Co-NCNTs的结构可以通过调节胞嘧啶-Co配位或碳化温度来控制。最佳的Co-NCNT具有均匀分布的NCNT（10 nm）、CoOx（5 nm）和CoNx部分，以协同促进电化学过程，并提供介孔纳米片结构，以保证快速的质量迁移和电子转移。结果，Co-NCNT显示出显著的ORR性能（在0.1M KOH电解质中起始电位为0.93 V），沿着显著的OER和HER活性。更重要的是，CoNx的引入改变了Co-NCNTs的活性中心，增强了金属-碳的协同作用，降低了界面电阻，增强了复合材料的强度，从而使Co-NCNTs具有显著的电催化活性。因此，本论文不仅展示了一种先进的多功能电催化剂，而且可以对多功能电催化剂的设计有更深的理解。
Carbon-metal composites are promising multifunctional electrocatalysts, but it is still challenging to prepare carbon-metal composites with tunable structure and strong metal-carbon interactions. Here, we present a unique gas-foaming assembly strategy to prepare cytosine-Co chelate derived Co and N codoped carbon nanotube (Co-NCNT). The structure for Co-NCNTs could be easily controlled by regulating cytosine-Co coordination or the carbonization temperature. The optimal Co-NCNT possesses homogeneous distributed NCNTs (10 nm), CoOx(5 nm) and CoNxmoieties to synergistically boost electrochemical processes, and offer mesoporous nanosheet architecture to guarantee fast mass migrate and electron transfer. As a result, Co-NCNT shows remarkable ORR performance (onset potential of 0.93 V in 0.1 M KOH electrolyte) along with significant OER and HER activity. More important, it was found that CoNxmoieties are responsible for the remarkable electrocatalytic activity in Co-NCNTs, because CoNxcould alter active center, enhance metal-carbon synergy, decrease interfacial resistance and reinforce the strength of composites. Therefore, this paper not just demonstrates an advanced multi-functional electrocatalyst, but could also give deep understanding on the designing of multifunctional electrocatalysts.