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规模化生产低成本和高效率的氧还原电催化剂在当今仍然是严峻的挑战。本文以三聚氰胺、三聚硫氰酸和硝酸钴作为原料,通过两步热解合成了一种新的氮、硫共掺杂的碳负载的钴@碳化钴(标记为MTC-0.1-900)氧还原催化剂。利用扫描电子显微镜、透射电子显微镜、X射线衍射、拉曼光谱、比表面分析和X射线光电子能谱分析对该催化剂进行了表征,并采用循环伏安和线性扫描伏安曲线等方法测试其在0.1 mol?L~(-1) KOH中的氧还原性能。结果显示,与商业Pt/C催化剂相比,MTC-0.1-900的起始电位和半波电位分别高出了29和5 mV。在-0.3 V(vs Ag/AgCl)电位下工作12000 s后,MTC-0.1-900催化剂的电流可达到起始电流的97.1%,高于Pt/C催化剂的76.7%,显示出该催化剂具有更稳定的性能。抗甲醇实验表明,MTC-0.1-900的对氧还原的选择性也要优于Pt/C。该催化剂优良的性能为金属空气电池阴极材料提供了一种减少或者取代Pt的新选择。
Large-scale production of low cost and high efficiency oxygen reduction electrocatalysts remains a serious challenge today. In this paper, a new nitrogen and sulfur co-doped carbon supported cobalt @ cobalt carbide (labeled as MTC-0.1-900) was synthesized by two-step pyrolysis using melamine, trithiocyanuric acid and cobalt nitrate as starting materials Restore the catalyst. The catalyst was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy, surface area analysis and X-ray photoelectron spectroscopy. The cyclic voltammetry and linear sweep voltammetry Oxygen reduction performance in 0.1 mol? L ~ (-1) KOH. The results show that the onset and half-wave potentials of MTC-0.1-900 are 29 and 5 mV higher, respectively, than commercial Pt / C catalysts. After 12000 s at -0.3 V (vs Ag / AgCl), the current of MTC-0.1-900 catalyst reached 97.1% of the initial current, which is higher than 76.7% of the Pt / C catalyst, indicating that the catalyst has more Stable performance. Anti-methanol experiments showed that the selectivity of MTC-0.1-900 to oxygen reduction is better than that of Pt / C. The excellent performance of the catalyst provides a new choice for metal-air battery cathode materials to reduce or replace Pt.