碱性介质中纳米薄膜Ru电极上CO吸附的异常红外效应

Abnormal Infrared Effects (AIREs) of nm-Ru/GC Electrode Towards CO Adsorption in Alkaline Solutions

研制纳米级厚度的Ru薄膜电极 ,并运用电化学原位FTIR反射光谱研究碱性介质中CO的吸附。检测到CO以线型吸附态为主 ,但也存在少量桥式吸附态 ,分别在 196 0和 1780cm-1附近给出红外吸收谱峰。发现纳米Ru膜电极具有异常红外效应 ,即CO谱峰方向倒反 ,强度增强和半峰宽增加。测得在碱性溶液中吸附态CO的红外吸收被增强了 33倍 ,其增强因子是酸性溶液中的两倍左右。

The adsorption of CO on electrode of nanometer thin film of Ru in 0 1 mol·L -1 NaOH solution was studied by using in situ FTIR spectroscopy.The results revealed that the adsorbed CO in alkaline solutions is mainly in linear bonded form that yields IR absorption at around 1 960 cm -1 ,and a small portion of bridge bonded CO was also determined near 1 780 cm -1 .The band centers of CO L and CO B have been red shifted respectively about 50 and 60 cm -1 in comparision with the values measured in acid medium.The enhancement factor of IR absorption of CO on nm Ru/GC electrode has been measured at 33 in 0 1 mol·L -1 NaOH solution,which is more than 2 times larger than the value determined in a 0 1 MH 2SO 4 solution.