物理化学学报
物理化學學報
물이화학학보
ACTA PHYSICO-CHIMICA SINICA
2015年
2期
199-203
,共5页
热依莎·多里坤%阳耀月%蔡文斌
熱依莎·多裏坤%暘耀月%蔡文斌
열의사·다리곤%양요월%채문빈
Pt纳米晶%CO%电吸附%电氧化%表面增强红外吸收光谱
Pt納米晶%CO%電吸附%電氧化%錶麵增彊紅外吸收光譜
Pt납미정%CO%전흡부%전양화%표면증강홍외흡수광보
Pt nanocrystal%CO%Electrosorption%Electrooxidation%Surface enhanced infrared absorption spectroscopy
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.
為理解Pt納米晶(NCs)錶麵上吸附與反應的結構效應,本文利用電化學衰減全反射-錶麵增彊紅外吸收光譜(ATR-SEIRAS)初步研究瞭{100}優先取嚮的Pt納米晶錶麵CO電吸附和電氧化.閤成併清洗過的Pt納米晶在硫痠溶液中的循環伏安圖齣現瞭四對氧化還原峰,其中位于0.26和0.36 V的峰分彆對應于短程有序和長程有序Pt{100}上的氫吸脫附.利用Bi、Ge不可逆吸附法估算齣Pt{100}和Pt{111}納米晶籌分彆佔34%和17%.在原位紅外光譜研究中,首次分辨齣線性吸附的CO (COL)物種在Pt納米晶的三箇基礎小晶麵上的振動譜峰.動電位光譜分析結果錶明Pt{110}上吸附的COL優先電氧化,其次{111}上的COL髮生氧化,而Pt{100}上COL氧化過電位最高.
위리해Pt납미정(NCs)표면상흡부여반응적결구효응,본문이용전화학쇠감전반사-표면증강홍외흡수광보(ATR-SEIRAS)초보연구료{100}우선취향적Pt납미정표면CO전흡부화전양화.합성병청세과적Pt납미정재류산용액중적순배복안도출현료사대양화환원봉,기중위우0.26화0.36 V적봉분별대응우단정유서화장정유서Pt{100}상적경흡탈부.이용Bi、Ge불가역흡부법고산출Pt{100}화Pt{111}납미정주분별점34%화17%.재원위홍외광보연구중,수차분변출선성흡부적CO (COL)물충재Pt납미정적삼개기출소정면상적진동보봉.동전위광보분석결과표명Pt{110}상흡부적COL우선전양화,기차{111}상적COL발생양화,이Pt{100}상COL양화과전위최고.
Electrochemical attenuated total reflection-surface enhanced infrared absorption spectroscopy (ATR-SEIRAS) has been used to investigate the facet-dependent adsorption and oxidation of CO on the{100}-preferred Pt nanocrystals (NCs). The cyclic voltammogram for the synthesized and then cleaned Pt NCs in a sulfuric acid solution displayed four pairs of redox peaks. The peaks located at 0.26 and 0.36 V were attributed to interfacial hydrogen electro-adsorption/desorption processes on the short-and long-range Pt{100}domains, respectively. Furthermore, the Pt{100}and Pt{111}domains were estimated to account for 34%and 14%of the active sites on the surfaces of the Pt NCs, respectively, based on Bi and Ge irreversible adsorption methods. Potential-dependent spectral features can be used to differentiate the adsorption and oxidation processes of linearly adsorbed CO (COL) species on the three basic planes of the Pt NCs. COL species on the Pt{110}facets were oxidized preferential y, fol owed sequential y by those on the Pt{111}and Pt{100}facets. COL on Pt{100}required the highest overpotential for their oxidation.