高活性位点密度Fe-N共掺杂碳纳米片的制备及氧还原性能

Preparation and Oxygen Reduction Performance of Fe,N co-Doped Carbon Nanoplate with High Density of Active Sites

从三聚氰胺和均苯四甲酸酐单体出发,通过熔融盐法合成了三嗪结构聚酰亚胺纳米片,借助类石墨相氮化碳(g-C3N4)与铁离子的配位作用,经高温热处理形成了高效掺杂的Fe-N/C催化剂.研究结果表明,该催化剂为表面粗糙的纳米片结构,比表面积高达1794 m^2/g.通过g-C3N4的引入和含量的调控,催化剂中铁元素的掺杂量最高可达1.13%(摩尔分数),为未引入g-C3N4的3.3倍,其原因可归结于g-C3N4配位锚定了铁离子,其较强的配位作用可以避免高温热处理时铁元素的迁移和聚集.该催化剂在酸性条件下氧还原反应半波电位为0.79V,10000周加速测试后的半波电位衰减了30mV,表现出较好的氧还原活性.

Fe,N co-doped carbon nanoplate catalyst with high active sites was developed via methods of polymerization of triazine polyimide and carbonization within melting salt of ZnCl2/KCl with the aid of g-C3N4 to anchor Fe^3+.The as-prepared NPT-C3N4-0.5 catalyst displays high specific surface area of 1794 m^2/g.The iron atoms uniformly distribute in the carbon skeleton with an increased doping amount up to the molar percentage of 1.13%,3.3 times of the one without g-C3N4,which can be attributed to the coordination between g-C3N4 and iron to decrease its aggregation under high temperature.The catalyst exhibits excellent catalytic activity for oxygen reduction reaction(ORR)in acid media.Typically,the half-wave potential(E1/2)of the catalyst can reach up to 0.79V(vs.RHE)and only decreases by 30 mV after 10000 potential cycles of accelerated durability test in acid media,showing high activity towards ORR.