论文摘要
Metal-nitrogen doped carbon catalysts（M-N/C） with abundantly accessible M-Nxsites, particularly single metal atom M-N/C（SAM-N/C）, have been developed as a substitute for expensive Pt-based catalysts.These catalysts are used to increase the efficiency of otherwise sluggish oxygen reduction reactions（ORR） and hydrogen evolution reactions（HER）. However, although the agglomerated metal nanoparticles are usually easy to form, they are very difficult to remove due to the protective surface-coating carbon layers, a factor that significantly hampers SAM-N/C fabrication. Herein, we report a one-step pyrolysis approach to successfully fabricate single cobalt atom Co-N/C（SACo-N/C） by using a Co2+-SCN-coordination compound as the metal precursor. Thanks to the decomposition of Co2+-SCN-compound at lower temperature than that of carbon layer deposition, Co-rich particles grow up to larger ones before carbon layers formation. Even though encapsulated by the carbon layers, it is difficult for the large Co-rich particle to be completely sealed. And thus, it makes the Co atoms possible to escape from incomplete carbon layer, to coordinate with nitrogen atoms, and to form SACo-N/C catalysts. This SACo-N/C exhibits excellent performances for both ORR（half-wave potential of 0.878 V） and HER（overpotential at 10 mA/cm2 of178 m V）, and is thus a potential replacement for Pt-based catalysts. When SACo-N/C is integrated into a Zn-O2 battery, battery with high open-circuit voltage（1.536 V） has high peak power density（266 mW/cm2）and large gravimetric energy density（755 mA h/gZn） at current densities of 100 mA/cm2. Thus, we believe that this strategy may offer a new direction for the effective generation of SAM-N/C catalysts.
论文目录
文章来源
类型: 期刊论文
作者: Yao Wang,Linhui Chen,Zhanxin Mao,Lishan Peng,Rui Xiang,Xianyi Tang,Jianghai Deng,Zidong Wei,Qiang Liao
来源: Science Bulletin 2019年15期
年度: 2019
分类: 基础科学,工程科技Ⅰ辑,工程科技Ⅱ辑
专业: 无机化工,有机化工,电力工业
单位: Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, College of Chemistry and Chemical Engineering. Chongqing University,Institute of New-Energy and Low-Carbon Technology, Sichuan University,Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University
基金: supported by the National Key Research and Development Program of China(2016YFB0101202),the National Natural Science Foundation of China(21761162015,91534205,21436003),the Fundamental Research Funds for the Central Universities
分类号: TQ426;TM911.41
页码: 1095-1102
总页数: 8
文件大小: 1080K
下载量: 15