摘要
现场表面拉曼光谱结果显示,在0.2mol·L-1Na2MoO4,pH=4.0的溶液中,电位正于0.5V(vsSCE)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-1FeSO4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.
The Fe-Mo alloy induced-codeposition has been studied by in istu 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.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
1998年第12期1074-1079,共6页
Acta Physico-Chimica Sinica
关键词
现场表面
拉曼光谱
铁钼合金
诱导共沉积
In situ surface Raman spectroscopy, Fe-Mo alloy, Induced-codeposition