化学学报 ›› 2020, Vol. 78 ›› Issue (4): 330-336.DOI: 10.6023/A19110400 上一篇    下一篇

研究论文

动态氢气泡/牺牲铜模板法制备蜂窝AuPtCu电催化剂用于甲酸氧化

陈莹莹, 刘欢, 程彦, 谢青季   

  1. 湖南师范大学化学化工学院 化学生物学及中药分析教育部重点实验室 长沙 410081
  • 投稿日期:2019-11-12 发布日期:2020-03-12
  • 通讯作者: 谢青季 E-mail:xieqj@hunnu.edu.cn
  • 基金资助:
    项目受国家自然科学基金(Nos.21675050,21475041和21775137)、湖南芙蓉学者计划(2011)和湖南省科技厅基金(No.2016SK2020)资助.

Preparation of Honeycomb-structured AuPtCu Electrocatalyst by Dynamic Hydrogen Bubble and Sacrificial Cu Templates for Oxidation of Formic Acid

Chen Yingying, Liu Huan, Cheng Yan, Xie Qingji   

  1. Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research(Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081
  • Received:2019-11-12 Published:2020-03-12
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Nos. 21675050, 21475041 and 21775137), Hunan Lotus Scholars Program (2011) and Foundation of the Science & Technology Department of Hunan Province (No. 2016SK2020).

微/纳多孔金属材料具有高比表面积等优点,在电化学等领域广受关注.本工作通过动态氢气泡模板法,在镀金玻璃碳电极(Aupla/GCE)上电沉积三维蜂窝状多孔纳米AuPtCu (3DHPN-AuPtCu)复合材料,再阳极溶出Cu,制备了3DHPN-AuPtCu/Aupla/GCE.采用循环伏安法(CV)、金相显微镜、扫描电子显微镜、能量色散谱和电感耦合等离子体-原子发射光谱等手段表征了相关修饰电极.所制3DHPN-AuPtCu/Aupla/GCE在含0.2 mol/L HCOOH的0.5 mol/L H2SO4水溶液中,电催化氧化甲酸的峰电流密度为12.5 mA·cmPt-2(CV,-0.3~1.0 V,50 mV/s),优于有关对照电极和很多已报道的Pt复合物修饰电极,表明通过这种动态氢气泡/牺牲铜双模板法可制备出电催化性能优异的金属蜂窝结构.

关键词: 动态氢气泡模板, 牺牲铜模板, 蜂窝结构AuPtCu电催化剂, 甲酸氧化

Improving the performance of electrocatalytic formic acid oxidation is the key issue to develop high-performance direct formic acid fuel cells (DFAFC). Pt-based and Pd-based materials are the important electrocatalysts for formic acid oxidation. Micro/nano-porous metal materials are widely concerned in the electrochemistry field due to the high specific electrode-surface area. The dynamic hydrogen bubble template (DHBT) method has been widely used for preparing the three-dimensional honeycomb-like porous nano-metals (3DHPNMs). However, as far as we know, the use of a sacrificial metal template to prepare the 3DHPNMs with improved performance for the electrocatalytic oxidation of small organic molecules has not been reported. Herein, a three-dimensional honeycomb-like porous nano-AuPtCu (3DHPN-AuPtCu) composite was electrodeposited on a gold-plated glassy carbon electrode (Aupla/GCE) by the DHBT method, followed by anodic stripping of Cu to yield a 3DHPN-AuPtCu/Aupla/GCE. The relevant modified electrodes were characterized by cyclic voltammetry (CV), metallographic microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy and inductively coupled plasma-atomic emission spectrometry. The SEM results clearly revealed that the use of the sacrificial Cu template can modulate the metal-honeycomb structure, and the 3DHPN-AuPtCu/Aupla/GCE can thus possess the better micro/nano-porous structure and the improved electrocatalytic performance than a Cu-template-free 3DHPN-AuPt/Aupla/GCE. In our opinion, the simultaneous electrodeposition of Cu can intervene in the electrodeposition of Au and Pt, and thus a new structure with more active sites exposed and the electrocatalysis performance improved can be obtained after the anodic stripping of electrodeposited Cu. As a result, the 3DHPN-AuPtCu/Aupla/GCE exhibited high anti-poisoning nature and high stability, because many discontinuous Pt atoms on this electrode can suppress the formation of adsorption-state COads during the electrocatalytic oxidation of formic acid. The electrocatalytic oxidation peak current density on 3DHPN-AuPtCu/Aupla/GCE in 0.5 mol/L aqueous H2SO4 containing 0.2 mol/L HCOOH was 12.5 mA·cmPt-2 (CV, -0.3~1.0 V, 50 mV/s), which is superior to the control electrodes and many reported Pt-based electrocatalysis electrodes. The suggested double- template method for preparing honeycomb-structured micro/nano-porous metal materials with improved performance has the potential for wider electrocatalysis and electroanalysis applications.

Key words: dynamic hydrogen bubble template, sacrificial Cu template, honeycomb-structured AuPtCu electrocatalyst, formic acid oxidation