论文部分内容阅读
为理解Pt纳米晶(NCs)表面上吸附与反应的结构效应,本文利用电化学衰减全反射-表面增强红外吸收光谱(ATR-SEIRAS)初步研究了{100}优先取向的Pt纳米晶表面CO电吸附和电氧化.合成并清洗过的Pt纳米晶在硫酸溶液中的循环伏安图出现了四对氧化还原峰,其中位于0.26和0.36 V的峰分别对应于短程有序和长程有序Pt{100}上的氢吸脱附.利用Bi、Ge不可逆吸附法估算出Pt{100}和Pt{111}纳米晶筹分别占34%和17%.在原位红外光谱研究中,首次分辨出线性吸附的CO(COL)物种在Pt纳米晶的三个基础小晶面上的振动谱峰.动电位光谱分析结果表明Pt{110}上吸附的COL优先电氧化,其次{111}上的COL发生氧化,而Pt{100}上COL氧化过电位最高.
In order to understand the structural effect of adsorption and reaction on the surface of Pt nanocrystals (NCs), the electrochemical behavior of the {100} preferentially oriented Pt nanocrystals was investigated by electrochemical reduction total reflection-surface enhanced infrared absorption spectroscopy (ATR-SEIRAS) Adsorption and electrooxidation.The four pairs of redox peaks appeared in the cyclic voltammograms of the synthesized and cleaned Pt nanocrystals in sulfuric acid solutions, and the peaks at 0.26 and 0.36 V correspond to the short-range order and long-range order Pt { 100}, respectively, and the Pt (100) and Pt {111} nanocrystals were estimated to be 34% and 17%, respectively, using Bi and Ge irreversible adsorption methods.In in-situ IR spectroscopy, The vibrational peaks of the CO (COL) species adsorbed on the three basal planes of Pt nanocrystals show that the COL adsorbed on Pt {110} is preferentially oxidized, followed by the COL on {111} Oxidation, and Pt {100} on the highest potential oxidation of COL.