化学学报 ›› 2015, Vol. 73 ›› Issue (7): 729-734.DOI: 10.6023/A15030195 上一篇    下一篇

研究论文

纳米碳纤维的表面改性对水电解析氢反应催化活性的影响

钮东方a, 丁勇a, 马智兴b, 王明辉b, 刘洲b, 张博文b, 张新胜a   

  1. a 华东理工大学化学工程联合国家重点实验室 上海 200237;
    b 华东理工大学材料科学与工程学院 上海 200237
  • 收稿日期:2015-03-21 出版日期:2015-07-14 发布日期:2015-06-29
  • 通讯作者: 张新胜 E-mail:xszhang@ecust.edu.cn
  • 基金资助:

    项目受国家自然科学基金(No. 21073061)和上海市大学生创新训练项目(No. S13028)资助.

Effects of Surface Modification of Carbon Nanofibers on Their Electro- catalytic Activity for Hydrogen Evolution Reaction of Water Electrolysis

Niu Dongfanga, Ding Yonga, Ma Zhixingb, Wang Minghuib, Liu Zhoub, Zhang Bowenb, Zhang Xinshenga   

  1. a State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237;
    b School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237
  • Received:2015-03-21 Online:2015-07-14 Published:2015-06-29
  • Supported by:

    Supporting information for this article is available free of charge via the Internet at http://sioc-journal.cn.Project supported by the National Natural Science Foundation of China (No. 21073061) and Shanghai university student innovative activities plan.

主要研究纳米碳纤维(CNF)的表面改性对析氢反应(HER)催化活性的影响. 首先采用一种简单易行的超声处理方法, 以混酸(浓硫酸和浓硝酸)为溶剂对CNF进行了表面化学处理, 以在其表面引入含氧(CNF-OX)官能团, 然后将CNF-OX在氨水中超声处理, 以引入含氮(CNF-ON)官能团, 以及将CNF-OX和硼酸混合经高温热解对CNF-OX进行掺B处理(B-CNF-OX). XPS结果表明, 超声处理可以成功地在CNF表面引入含氧和含氮官能团, 硼酸高温处理可以掺入B原子. 电化学测试结果表明, 经过表面改性后的CNF的HER催化性能都要好于未处理过的CNF-UN, 其中N掺杂的CNF-ON表现出最好的HER催化活性, 且CNF-OX经掺B处理后, B-CNF-OX的性能也较CNF-OX有所增强, 即三者的催化活性大小如下: CNF-OX

关键词: 纳米碳纤维, 析氢反应, 表面改性, 电催化性能, 电解水

The effects of surface modification of CNF on their electrocatalytic activity for hydrogen evolution reaction (HER) were investigated. Firstly, Oxygen-containing functional groups were introduced onto the CNF surface (labeled as CNF-OX) by a simple sonochemical oxidation in mixed acids (concentrated sulfuric acid and nitric acid) and then the nitrogen-containing functional groups were introduced onto the CNF-OX surface (labeled as CNF-ON) by sonochemical treatment in ammonia, and the B-doped CNF was synthesized by mixing CNF-OX and boric acid in a ratio following by pyrolysis at 800 ℃ under N2 atmosphere (labeled as B-CNF-OX). The XPS results showed that the ultrasonic treatments could introduce oxygen- and nitrogen-containing functional groups onto the CNF surface successfully, the oxygen atoms content of CNF-OX was increased from 1.96% to 6.01% compared to the untreated CNF (CNF-UN), and nitrogen atoms content of CNF-ON was increased from 0% to 1.02% compared to CNF-OX. The pyrolysis of boric acid could introduce B element onto the CNF-OX surface where the B atoms content of B-CNF-OX was 1.00%. The linear sweep voltammetry (LSV) test results showed that the HER electrocatalytic activity of the modified CNFs were higher than CNF-UN, and among them CNF-ON had the highest electrocatalytic activities for HER than the others, the onset overpotential of CNF-ON was 344 mV, which shifted 240 mV positively compared to CNF-UN, and the electrocatalytic activity of B-CNF-OX was enhanced by B-doping treatment compared to CNF-OX. The Tafel test indicated CNF-ON had smallest Tafel slop of 154 mV/dec and largest exchange current density of 6.68 μA/cm2. The electrochemical impedance spectroscopy (EIS) was carried out to investigate the complex interfacial properties of the CNFs modified electrode, and the results showed that CNF-ON had the smallest charge transfer resistance of 1578 Ω among all the catalysts, which means the nitrogen-doped CNF had higher activity than the oxygen- and boron-doped CNF. All above indicated that the doping of heteroatom (O, B, N) onto the CNFs surface had effects on their electrocatalytic activity for HER, especially the introduction of N atom onto the CNF surface had excellent improvement.

Key words: carbon nanofibers, hydrogen evolution reaction, surface modification, electrocatalytic activity, water electrolysis