物理化学学报 >> 1998, Vol. 14 >> Issue (12): 1074-1079.doi: 10.3866/PKU.WHXB19981204

研究论文 上一篇    下一篇

现场表面拉曼光谱研究Fe-Mo合金诱导共沉积

牛振江, 姚士冰, 周绍民   

  1. 固体表面物理化学国家重点实验室,厦门大学化学系,厦门 361005
  • 收稿日期:1998-03-16 修回日期:1998-05-13 发布日期:1998-12-15
  • 通讯作者: 牛振江

In Situ Surface Raman Spectroscopy Study on Fe-Mo Alloy Induced-codeposition

Niu Zhen-Jiang, Yao Shi-Bing, Zhou Shao-Min   

  1. State Key Laboratory for Physical Chemistry of the Solid Surface,Department of Chemistry,Xiamen University,Xiamen 361005
  • Received:1998-03-16 Revised:1998-05-13 Published:1998-12-15
  • Contact: Niu Zhen-Jiang

摘要:

现场表面拉曼光谱结果显示,在0.2mol•L-1 Na2MoO4, pH=4.0的溶液中,电位正于0.5V(vs SCE)时只观察到多钼酸盐的拉曼峰(940、880和450cm-1).负于-0.5V时,出现中心位于730cm-1的宽峰.同时电极表面有蓝色膜生成.表明混合氧化态(MO(Ⅳ),MO(Ⅴ))氧化膜的形成.730cm-1的峰在-1.9V时仍然存在,说明氧化膜没有被进一步还原.在钼酸钠溶液中同时含有0.1mol•L-1 FeSO4和0.2mol•L-1柠檬酸时,中间态氧化膜的拉曼峰的中心移到740cm-1.且峰强度随着电位从-1.3V负移到-1.9V而逐渐减弱并最终消失.电极表面沉积层呈银白色,说明由于Fe2+的存在,钼的中间态氧化膜的结构发生了变化,能够被进一步还原形成Fe-Mo合金,表现出诱导共沉积的特征.

关键词: 现场表面拉曼光谱, Fe-Mo合金, 诱导共沉积

Abstract:

The Fe-Mo alloy induced-codeposition has been studied by in situ surface Raman spectroscopy. In the solution containing 0.2mol•L-1 Na2MoO4.pH=4.0.the Raman spectra showed three peaks at 940,880 and 450cm-1 corresponding to polymolybdated species on the surface at open circuit potential and -0.3V(vs SCE) at the potential-0.5V, new peaks at about 730, 560, 510, 470 cm-1 appeared in the spectra while a blue film was observed on the surface which can be attributed to mixed-oxidation molybdenum oxides formation. The peak at 730cm-1did not disappear even the potential moved to -1.9V, indication the film annot be further reduced. But in the solution of Na2MoO4 containing 0.1 mol•L-1 FeSO4 and 0.2mol•L-1 citric acid, the peak of mixed-oxidation oxides shifted to 740cm-1 and this peak could fade away gradually in potential region from -1.3 to -1.9V while a silver-white deposit emerged on the surface The results showed that the structure of mixed-oxidation Mo oxides film codeposited with Fe2+ was different from that of the film deposited without Fe2+. The former can be further reduced to form Fe-Mo alloy.

Key words: In situ surface Raman spectroscopy, Fe-Mo alloy, Induced-codeposition