摘要
通过共沉淀法合成了四方相Ce0.25Zr0.75O2固溶体,采用X射线粉末衍射仪(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)表征了固溶体的结构,并以氮气和水为原料,在室温、0.1 mol/L Na2SO4电解质中研究了固溶体的电化学催化合成氨性能。结果表明,Ce0.25 Zr0.75O2表现出了优异的电化学氮还原催化性能,在-0.6 V(vs.Ag/AgCl)时法拉第效率最高,达到64%,此时氨合成速率为7.3×10^-11 mol/(s·cm^2);在-0.7V(vs.Ag/AgCl)时,氨合成速率最高,为1.03×10^-10 mol/(s·cm^2),此时法拉第效率为42.2%。这可能与Ce0.25Zr0.75O2固溶体的四方相结构、晶格结构的变化及形成的高度缺陷的结构有关;另外,Ce0.25Zr0.75O2还能有效抑制析氢副反应进行,从而提高其法拉第效率。
A Ce0.25Zr0.75O2 solid solution has been synthesized by a co-precipitation method,and characterized by XRD,SEM and TEM.Its catalytic performance in the electrochemical synthesis of ammonia was investigated in 0.1 mol/L Na2SO4 as electrolyte using N2 and H2O as raw materials at room temperature.The results showed that Ce0.25 Zr0.75O2 exhibited excellent electrochemical nitrogen reduction catalytic performance.At-0.6 V(vs.Ag/AgCl),the Faraday efficiency reached a maximum value of 64%with an ammonia synthesis rate of 7.3×10^-11 mol/(s·cm^2);at-0.7V(vs.Ag/AgCl),the ammonia synthesis rate reached a maximum of 1.03×10^-10 mol/(s·cm^2)with a Faraday efficiency of 42.2%.The excellent performance of the Ce0.25Zr0.75O2 solid solution may be attributed to its tetragonal structure,changes in the lattice structure and the formation of highly defective structures.In addition,Ce0.25Zr0.75O2 can effectively inhibit hydrogen evolution side effects,thereby improving its Faraday efficiency.
作者
林忻
何小波
银凤翔
李国儒
LIN Xin;HE XiaoBo;YIN FengXiang;LI GuoRu(College of Chemical Engineering,Beijing University of Chemical Technology,Beijing 100029;Jiangsu Key Laboratory of Green Catalytic Materials and Technology,School of Petrochemical Engineering,Changzhou University,Changzhou 213164;Changzhou Institute of Advanced Materials,Beijing University of Chemical Technology,Changzhou 213164,China)
出处
《北京化工大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第4期9-15,共7页
Journal of Beijing University of Chemical Technology(Natural Science Edition)
基金
江苏省自然科学基金(BK20161200)。
关键词
电化学
合成氨
氮还原反应
电催化
铈锆固溶体
electrochemistry
ammonia synthesis
nitrogen reduction reaction
electrocatalysis
cerium zirconium oxide solid solution
