Acta Chim. Sinica ›› 2015, Vol. 73 ›› Issue (7): 729-734.DOI: 10.6023/A15030195 Previous Articles     Next Articles

Article

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.

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