松树枝状双金属Ag-Cu颗粒的制备与电活性  

Fabrication and Electroactivity of Pine Branch-Like Binary Ag-Cu Nanoparticles

作　　者：易清风[1] 李磊[1] 宋李红[1] 牛凤娟[1] 

机构地区：[1]湖南科技大学化学化工学院,湘潭411201

出　　处：《无机化学学报》2010年第9期1600-1604,共5页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No20876038);教育部留学回国人员科研启动基金(No20071108);湖南省科技厅科技计划(No2009GK3084)资助项目

摘　　要：利用恒电位电解技术,直接从无支持电解质的AgNO3和Cu(NO3)2混合溶液中,在钛片表面上沉积具有松树枝状结构的双金属Ag-Cu纳米颗粒。SEM图像表明,树枝长度随铜比例的增加而增加;随着电解的不断进行,双金属纳米颗粒直接沉积于树叶顶端,形成花蕊芯状结构。松树枝状结构的形成是Ag+和Cu2+的扩散过程与电迁移过程共同作用的结果。研究了肼在这种双金属Ag-Cu纳米颗粒上的循环伏安特性,结果表明,肼在这种以钛为基体的树枝状双金属Ag79Cu21,Ag71Cu29和Ag54Cu46纳米电极表面上的吸附为多层吸附,由此建立超低浓度肼的电化学检测法,在1mol·L-1NaOH溶液中的检测下限分别为0.0941、0.0369和0.264μmol·L-1。From the mixture of AgNO3 and Cu（NO3）2 without supporting electrolyte, pine branch-like binary Ag-Cu nanoparticles were deposited on the Ti surface using simple chronoamperometric technique. Their SEM images show that the length of pine branches increases with electro-deposition time and copper content in the mixture of AgNO3 and Cu（NO3）2. It was also observed that the increase of electro-deposition time resulted in the deposition of binary Ag-Cu nanoparticles on the top of pine leaves to form a pistil-like texture. The possible formation mechanism of the pine branch-like structure was related to both electro-migration and diffusion processes of metal ions （Ag＋ ＋ Cu2＋）. Therefore, it was possible to control both the length of branches and pine leaves by choosing appropriate compositions of the Ag＋ to Cu2＋ and electrodeposition time. A multi-layer adsorption mechanism of hydrazine on these Ti-supported binary Ag-Cu electrocatalysts was proposed according to the cyclic voltammograms in alkaline solutions. An electrochemical detection of ultra-low concentration of hydrazine was founded on the basis of cyclic voltammetric measurements. The detection limits of hydrazine in 1 mol·L-1 NaOH at Ag79Cu21, Ag71Cu29 and Ag54Cu46 were 0.094 1, 0.036 9 and 0.264 μmol·L-1 respectively. The prepared pine branch-like binary Ag-Cu nanoparticles presented high stability on the Ti substrate in alkaline solutions.

关 键 词：松树枝状纳米颗粒 双金属Ag-Cu 肼检测 电沉积 

分 类 号：O614.121[理学—无机化学] O614.122[理学—化学]