高氮含量多孔碳的制备、热处理及氧还原性能  

Preparation,Heat-Treatment and Oxygen Reduction Performance of Porous Carbon with High Nitrogen Content

作　　者：柯源 胡稳 方晗 田爽 王升高[1] KE Yuan;HU Wen;FANG Han;TIAN Shuang;WANG Shenggao(Hubei Key Laboratory of Plasma Chemical and Advanced Materials(Wuhan Institute of Technology),Wuhan 430205,China)

机构地区：[1]等离子体化学与新材料湖北省重点实验室(武汉工程大学),湖北武汉430205

出　　处：《武汉工程大学学报》2021年第6期626-631,共6页Journal of Wuhan Institute of Technology

基　　金：国家自然科学基金(51272187,1704288)。

摘　　要：采用快速高温碳化法成功制备了具有海绵结构、氮原子摩尔分数高达7.5%的氮掺杂多孔碳材料(N-PC),然后对其进行惰性氛围高温脱氮处理,获得氮原子摩尔分数为2.5%、起始电位-44 mV、半峰电位-134 mV、极限电流密度-4.5 mA·cm^(-2)的样品。分别用场发射扫描电子显微镜、X射线光电子能谱和Raman光谱对N-PC材料进行了表征。采用伏安法测定了材料在O_(2)饱和0.1 mol/LKOH电解液中的氧还原反应(ORR)性能。结果发现,高吡啶氮、吡咯氮摩尔分数的多孔碳材料不具备优异的氧还原性能,而脱氮后的多孔碳材料因有较多的结构缺陷,暴露出了更多的活性位点,表现出较好的电化学性能。N-PC具有与Pt/C催化剂相近的电催化性能,而且具有比Pt/C催化剂更高的耐甲醇能力和更好的稳定性。因此,N-PC可以作为铂催化剂在ORR领域的一个非常突出的替代选择。A nitrogen-doped porous carbon material(N-PC)with a sponge structure and nitrogen atom mole fraction up to 7.5%was successfully prepared by high-temperature carbonization.Then it was subjected to high-temperature denitrification treatment in an inert atmosphere to obtain a sample with nitrogen atom mole fraction of 2.5%,which has an onset potential of-44 mV(vs.Ag/AgCl),half-wave potential of-134 mV(vs.Ag/AgCl),limiting current density of-4.5 mA·cm^(-2) and electron transfer number of 3.9.The N-PC materials were characterized by field emission scanning electron microscopy,X-ray photoelectron spectroscopy and Raman spectroscopy.The rotating disk electrode voltammetry was used to estimate the oxygen reduction reaction(ORR)performance of N-PC in O_(2)-saturated 0.1 mol/L KOH electrolyte.The results show that porous carbon materials with high atom mole fraction of pyridine nitrogen and pyrrole nitrogen do not have excellent oxygen reduction performance,while the porous carbon materials after nitrogen removal have more structural defects,exposing more active sites,and exhibiting better electrochemical performance.The electrocatalytic performance of N-PC is similar to that of Pt/C catalysts,and it has higher methanol resistance and better stability than Pt/C catalysts.Therefore,N-PC can be used as a very prominent alternative to platinum catalysts in the ORR.

关 键 词：氮掺杂 多孔碳 氧还原反应 热处理 

分 类 号：O643[理学—物理化学]