运用电化学循环伏安法在玻碳载体上制备纳米级厚度的Pt薄膜电极 ,用STM表征电极表面的形貌 ,测定了电沉积层的厚度、表面积和Pt载量 .同时 ,应用电化学循环伏安法和原位FTIR反射光谱研究了乙醇在碱性介质中的吸附和氧化行为 .结果表明 ,乙醇氧化的主要产物是CH3COO- ,仅存在少量乙醛 ,并未观察到任何CO谱峰 .与酸性介质中乙醇氧化的双途径机理不同 ,碱性介质中乙醇氧化未经过解离吸附中间过程
陈国良
,
孙世刚
,
陈声培
,
周志有
. 乙醇在碳载Pt纳米薄膜电极上吸附氧化过程研究Ⅰ.碱性介质中循环伏安和原位FTIR反射光谱[J]. 电化学, 2000
, 6(4)
: 406
-411
.
DOI: 10.61558/2993-074X.3230
The electro_oxidation of ethanol on nm_Pt/GC electrode in alkaline solutions containing 0.02 mol·L -1 NaOH+0.1 mol·L -1 CH 3CH 2OH was investigated by using cyclic voltammetry and in_situ FTIR spectroscopy. The experimental results demonstrated that the main product of ethanol oxidation is CH 3COO -,only very small amount of CH 3CHO has been determined simultaneously. In contrast with the dual path reaction mechanism for the oxidation of ethanol in acid media,the oxidation of ethanol in alkaline media didn't pass through the dissociative adsorption,and no adsorbed species could be determined even using a nm_Pt/GC electrode that gives rise to enhancement of IR absorption of adsorbates.
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