以Au粒子(55nm)为核,抗坏血酸为还原剂,将不同量的Pt沉积在Au核上,制得可控壳层厚度(0.3～6nm)的Pt包Au纳米粒子(Aucore@Ptshell).用紫外-可见吸收光谱、扫描电镜(SEM)、透射电镜(TEM)和电化学循环伏安法等观测Aucore@Ptshell纳米粒子的表面形貌、结构和性能.另以SCN-为探针,考察了Pt壳厚度对Aucore@Ptshell纳米粒子SERS信号的影响.结果表明,SCN-离子的SERS信号强度随Pt壳厚度的增加呈指数衰减,当Pt壳厚度为1.4nm时,Aucore@Ptshel纳米粒子表现出铂良好的电化学性能,又具有较强的SERS活性.
钟艳
,
颜亮亮
,
饶贵仕
,
邓小聪
,
温飞鹏
,
徐金龙
,
钟起玲
. 不同Pt壳厚度Au_(core)@Pt_(shell)纳米粒子SERS效应[J]. 电化学, 2010
, 16(3)
: 300
-304
.
DOI: 10.61558/2993-074X.2053
By using Au nanoparticles with a diameter of 55 nm as the core and ascorbic acid as the reductant, Aucore@ Ptshell nanoparticles of controllable Pt shell thickness( 0. 3 ～ 6 nm) were synthesized by controlling the concentration of [PtCl6]2 - ions. The ultraviolet-visible absorption spectrometry,scanning electron microscope ( SEM) ,transmission electron microscope ( TEM) ,high resolution transmission electron microscope ( HRTEM) , and electrochemical cyclic voltammetry were employed to determine surface morphology and structure of Aucore@ Ptshell. With SCN - ion as a probe,the effect of the thickness of the Pt shell on the SERS signals of Aucore@ Ptshell nanoparticles was investigated. It was found that the intensities of SERS signals decreased exponentially with the increase of Pt shell thickness. The result revealed that at a shell thickness of 1. 4 nm,the core-shell nanoparticles present the chemical property of the Pt shell and having a large SERS activity.
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