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  2012 

Keggin型缺位硅钨杂多阴离子的电化学性质及电催化还原H2O2

, PP. 174-180

Keywords: 缺位硅钨杂多阴离子,电催化,循环伏安,交流阻抗,过氧化氢还原

Full-Text   Cite this paper   Add to My Lib

Abstract:

应用循环伏安、方波伏安和交流阻抗法研究了Keggin型缺位硅钨杂多阴离子SiW11O398-(SiW11)在0.1mol?L-1NaHSO4+Na2SO4溶液中的电化学性质及其对H2O2还原的间接电催化作用。结果表明,SiW11的酸性水溶液在玻碳(GC)电极上显示两对可逆的还原-氧化波,对应的电荷迁移数均为1,且有2个质子参与反应。根据第1对波的还原峰电流与扫描速率平方根关系得到SiW11在溶液中的扩散系数Do为8.92×10-6cm2?s-1。SiW11对H2O2的还原具有明显的电催化活性,催化峰电位随溶液pH的降低而正移,峰电流增大。质子H+在催化反应中起协同促进作用。实验测定该电催化过程的均相准一级反应速率常数为0.30s-1。SiW11电催化还原H2O2的机理被认为该反应是经过形成所谓“七配位过氧化物”而发生的。

References

[1]  Rong C Y, Pope M T. Lacunary polyoxometalate anions are .pi.-acceptor ligands. Characterization of some tungstoruthenate(II,III,IV,V) heteropolyanions and their atom-transfer reactivity [J]. Journal of the American Chemical Society, 1992, 114(8): 2932-2938.
[2]  Jorgensen K A. Transition-metal-catalyzed epoxidations [J]. Chemical Reviews, 1989, 89(3): 431-458.
[3]  Josrgensen K A, Schistt B. Metallaoxetanes as intermediate in oxygen-transfer reactions - reality or fiction? [J]. Chemical Reviews, 1990, 90(8): 1483-1506.
[4]  Drago R S. Homogeneous metal-catalyzed oxidations by O2 [J]. Coordination Chemical Reviews, 1992, 117(22): 185-213.
[5]  Wang C T, Hua Y J, Li G R, et al. Indirect cathodic electrocatalytic degradation of dimethylphthalate with PW11O39Fe(III)(H2O)4? and H2O2 in neutral aqueous medium [J]. Electrochimica Acta, 2008, 53(16): 5100-5105.
[6]  Wang C T, Hua Y J, Tong Y X. A novel Electro-Fenton-Like system using PW11O39Fe(III)(H2O)4? as an electrocatalyst for wastewater treatment [J]. Electrochimica Acta, 2010, 55(22): 6755-6760.
[7]  Hua Y J (华英杰), Wang C T (王崇太), Tong Y X (童叶翔), et al. Electrocatalytic degradation of nitrobenzene with Keggin-type PW11O39Fe(III)(H2O)4- [J]. Acta Chimica Sinica (化学学报), 2009, 67(23): 2650-2654.
[8]  Wang C T (王崇太), Hua Y J (华英杰), Hua S Y (华淑艳), et al. Photocatalytic degradation of nitrobenzene with Keggin-type Fe(III)-Substituted Heteropolyanion PW11O39Fe(III)(H2O)4- [J]. Acta Chimica Sinica (化学学报), 2010, 68(11): 1037-1042.
[9]  Wang C T (王崇太), Hua Y J (华英杰), Li G R (李高仁), et al. Electrocatalytic oxidation of 4-methylpyridine by Cr(III)-substituted phosphorus Heteropolytungstate [J]. Acta Chimica Sinica (化学学报), 2008, 66(8): 835-840.
[10]  Server-Carrio J, Bas-Serra J, Gonzalez-Nunez M E, et al. Synthesis, characterization, and catalysis of β3-[(CoIIO4)W11O31(O2)4]10-, the first Keggin-based true heteropoly dioxygen(Peroxo) anion. Spectroscopic (ESR, IR) evidence for the formation of superoxo polytungstates [J]. Journal of the American Chemical Society, 1999, 121(5): 977-984.
[11]  Lei P X, Chen C C, Yang J, et al. Degradation of dye pollutants by immobilized polyoxometalate with H2O2 under visible-light irradiation [J]. Environmental Science &Technology, 2005, 39(21): 8466-8474.
[12]  Hua Y J (华英杰), Wang C T (王崇太), Li G R (李高仁), et al. Electrochemical properties of the Keggin-type lacunary heteropolytungstate anion and its electrocatalysis for H2O2 reduction [J]. Acta Chimica Sinica (化学学报), 2009, 67(8): 795-800.
[13]  Hua Y J (华英杰), Wang C T (王崇太), Wei J C(韦吉崇), et al. Electrocatalytic degradation of nitrobenzene by Keggin-type lacunary heteropolyanion PW11O397- [J]. Acta Chimica Sinica (化学学报), 2010, 68(19): 1961-1964.
[14]  Brevard C, Schimpf R, Tourné G, et al. Tungsten-183 NMR: A complete and unequivocal assignment of the tungsten-tungsten connectivities in heteropolytungstates via two-dimensional 183W NMR techniques [J]. Journal of the American Chemical Society, 1983, 105(24): 7059-7063.
[15]  Sadakane M, Steckhan E. Investigation of the manganese-substituted α-Keggin-heteropolyanion K6SiW11O39Mn(H2O) by cyclic voltammetry and its application as oxidation catalyst [J]. Journal of the Molecular Catalysis A: Chemistry, 1996, 114(3): 221-228.
[16]  Bard A J, Faulkner L R. Electrochemical method, principle and application (电化学方法,原理及应用) [M]. Beijing: Chemical Industry Press, 1986.
[17]  Wang C T (王崇太), Hua Y J (华英杰). Concise electro-chemistry principle and application (简明电化学原理及应用) [M]. Haikou: Hainan Press, 2008.
[18]  Toth J E, Melton J D, Cabelli D, et al. Electrochemistry and redox chemistry of aquaferrotungstosilicate, H2OFeIIISiW11O395- in the presence of hydrogen peroxide and hydroxyl [M]. Inorganic Chemistry, 1990, 29(10): 1952-1957.

Full-Text

Contact Us

service@oalib.com

QQ:3279437679

WhatsApp +8615387084133