本文研究BMIPF6离子液体中Au(111)和Pt(111)表面Ge的电沉积行为. 循环伏安法测试结果表明，在含0.1 mol·L-1 GeCl4的BMIPF6溶液Au(111)和Pt(111)表面均有两个与Ge沉积过程相关的还原峰. 第一个还原峰包含了Ge4+还原成Ge2+及Ge的欠电位沉积，第二个还原峰对应Ge的本体沉积. 现场扫描隧道显微镜研究结果表明，Ge在Au(111)和Pt(111)表面均有两层欠电位沉积. 第一层欠电位沉积厚度约为0.25 nm、形貌平整、带有缝隙的亚单层结构. 第二层欠电位沉积形貌相对粗糙的点状团簇结构. 该欠电位沉积过程伴随表面合金化.
The underpotential deposition (UPD) of germanium (Ge) in BMIPF6 ionic liquids on Au(111) and Pt(111) surfaces have been investigated by cyclic voltammetry (CV) and in-situ scannin tunneling microscopy (STM). The CV results show that there are two reduction peaks related to the electrodeposition of Ge. The first reduction peak appeared in the CV curve may cover the transformation of Ge4+ to Ge2+ and the UPD of Ge. The second reduction peak corresponds to the bulk deposition of Ge. In-situ STM study suggests that the two UPD layers of Ge are formed on Au(111) and Pt(111) surfaces. The first UPD layer is a film-like flat sub-monolayer with the thickness of 0.25 nm and some cracks. The second UPD layer is distributed on the first layer, which consists of some small Ge clusters with relatively rough morphology. The second UPD accompanies with surface alloying.
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