全部 标题 作者
关键词 摘要

OALib Journal期刊
ISSN: 2333-9721
费用:99美元

查看量下载量

相关文章

更多...
电化学  2010 

Pt电极上CO的同位素取代吸附机理研究

, PP. 324-333

Keywords: ,CO,偶极耦合作用,光谱拟合,电化学原位红外光谱,13COad/12CO同位素取代

Full-Text   Cite this paper   Add to My Lib

Abstract:

本文依据偶极耦合理论和相干势近似方法,合理选择粗糙电极上吸附分子的频率分布函数、一氧化碳(CO)吸附层的结构参数以及偶极耦合作用常数,对13CO/12CO同位素取代过程记录的红外光谱进行了拟合.研究发现,只有在拟合过程中引入低频CO分子优先取代,就可成功地模拟整个同位素取代过程的红外光谱随表面吸附的13CO/12CO组分的变化,并由此提出了吸附驱动的脱附机理,COad的脱附不是热激发脱附,而是吸附到表面的CO分子为其邻近位置COad的脱附提供能量.伸缩振动频率较低的COad处于台阶或缺陷位等较开阔的位置(尽管其吸附能较高),周围有较大的空间,利于来自溶液的CO分子的吸附,因此在台阶或缺陷位优先发生同位素的取代.

References

[1]  Severson M W,Russell A,Campbell D,et al.Vibration-al coupling in carbon monoxide adlayers on a platinum electrode[J].Langmuir,1987,3:202.
[2]  Hollins P,Pritchard J.Infrared studies of chemisorbed layers on single crystals[J].Progress in Surface Sci-ence,1985,19:275.
[3]  Geng B,Liu S,Cai J,et al.The mechanism and kinet-ics of cyanide-assisted carbon monoxide desorption from Pt electrodes:An infrared spectroscopic study[J].The Journal of Physical Chemistry C,2009,113:10326.
[4]  Heinen M,Chen Y X,Jusys Z,et al.CO adsorption ki-netics and adlayer build-up studied by combined ATR-FTIR spectroscopy and on-line DEMS under continuous flow conditions[J].Electrochimica Acta,2007,53:1279.
[5]  Wieckowski A,Rubel M,Gutiérrez C.Reactive sites in bulk carbon monoxide electro-oxidation on oxide-free platinum(111)[J].Journal of Electroanalytical Chemis-try,1995,382:97.
[6]  Watanabe S,Kinomoto Y,Kitamura F,et al.An infrared study of CO adsorbed on Pt(100)and Pt(110)elec-trodes:Dynamic aspects of CO at reconstructed surfaces[J].Journal of Electron Spectroscopy and Related Phe-nomena,1990,(54/55):1205.
[7]  Roth J D,Weaver M J.The electrooxidation of carbon monoxide on platinum as examined by surface infrared spectroscopy under forced hydrodynamic conditions[J].Journal of Electroanalytical Chemistry,1991,307:119.
[8]  Wasileski S A,Koper M T M,Weaver M J.Field-de-pendent chemisorption of carbon monoxide on platinum-group(111)surfaces:Relationships between binding energetics,geometries,and vibrational properties as as-sessed by density functional theory[J].The Journal of Physical Chemistry B,2001,105:3518.
[9]  Acres G J K,Frost J C,Hards G A,et al.Electrocata-lysts for fuel cells[J].Catalysis Today,1997,38:393.
[10]  Steele B C H,Heinzel A.Materials for fuel-cell technol-ogies[J].Nature,2001,414:345.
[11]  Brandon N P,Skinner S,Steele B C H.Recent advances in materials for fuel cells[J].Annual Review of Materi-als Research,2003,33:183.
[12]  Harrick N J.Internal reflection spectroscopy[M],Ossin-ing Harrick S-cientific Products,1967.
[13]  Kunimatsu K,Seki H,Golden W G,et al.Electrode/e-lectrolyte interphase study using polarization modulated FTIR reflection-absorption spectroscopy[J].Surf Sci,1985,158:596.
[14]  Kunimatsu K,Seki H,Golden W G,et al.Carbon mon-oxide adsorption on a platinum electrode studied by po-larization-modulated FT-IR reflection-absorption spec-troscopy:II.Carbon monoxide adsorbed at a potential in the hydrogen region and its oxidation in acids[J].Langmuir,1986,2:464.
[15]  Sun S G,Lipkowski J,Ross P N(Eds.).Electrocataly-sis[M].New York,Wiley-VCH,1998.
[16]  Miki A,Ye S,Osawa M.Surface-enhanced IR absorp-tion on platinum nanoparticles:an application to real-time monitoring of electrocatalytic reactions[J].Chem Commun,2002,1500
[17]  Osawa M.Handbook of vibrational spectroscopy[M].Chi-chester:Wiley,2002.785-799.
[18]  Chen Y X,Miki A,Ye S,et al.Formate,an active in-termediate for direct oxidation of methanol on Pt elec-trode[J].Journal of the American Chemical Society,2003,125:3680.
[19]  Zhou Z Y,Lin S C,Chen S P,et al.In situ step-scan time-resolved microscope FTIR spectroscopy working with a thin-layer cell[J].Electrochem Commun,2005,7:490.
[20]  Chen Y X,Heinen M,Jusys Z,et al.Kinetics and mechanism of the electrooxidation of formic acid-spec-troelectrochemical studies in a flow cell[J].Angew Chem Int Edit,2006,45:981.
[21]  Chen Y X,Ye S,Heinen M,et al.Application of in-situ attenuated total reflection-Fourier transform infrared spectroscopy for the understanding of complex reaction mechanism and kinetics:Formic acid oxidation on a Pt film electrode at elevated temperatures[J].The Journal of Physical Chemistry,2006,110:9534.
[22]  Tian Z Q,Ren B,Li J F,et al.Expanding generality ofsurface-enhanced Raman spectroscopy with borrowing SERS activity strategy[J].Chem Commun,2007:3514.
[23]  Persson B N J,Ryberg R.Vibrational interaction be-tween molecules adsorbed on a metal surface:The di-pole-dipole interaction[J].Physical Review B,1981,24:6954.
[24]  Severson M W,Stuhlmann C,Villegas I,et al.Dipole-dipole coupling effects upon infrared-spectroscopy of compressed electrochemical adlayers-application to the Pt(111)/Co system[J].J Chem Phys,1995,103:9832.
[25]  Persson B N J.Absorption of phonons by molecules adsorbed on metal surfaces[J].Solid State Communi-cations,1979,30:163.
[26]  Chang S C,Weaver M J.Coverage-dependent dipole coupling for carbon-monoxide adsorbed at ordered plat-inum(111)-aqueous interfaces-structural and electro-chemical implications[J].J Chem Phys,1990,92:4582.
[27]  Heinen M,Chen Y X,Jusys Z,et al.Room temperature COad desorption/exchange kinetics on pt electrodes—A combined in situ IR and mass spectrometry study[J].Chemphyschem,2007,8:2484.
[28]  Geng B,Cai J,Liang S,et al.Temperature effects on CO adsorption/desorption at Pt film electrodes:an electrochemical in situ infrared spectroscopic study[J].Physical Chemistry Chemical Physics,accept,2010,36:10888.
[29]  Iwasita T,Nart F C,Rodes A,et al.Vibrational spec-troscopy at the electrochemical interface[J].Electro-chimica Acta,1995,40:53.

Full-Text

Contact Us

service@oalib.com

QQ:3279437679

WhatsApp +8615387084133