Steady-state voltammetry for the reduction of labile metal complexes in the absence and presence of different concentrations of supporting electrolyte

被引:12
作者
Daniele, S [1 ]
Bragato, C [1 ]
Baldo, MA [1 ]
机构
[1] Univ Venice, Dept Chem Phys, I-30123 Venice, Italy
关键词
steady-state voltammetry; microelectrodes; labile metal complexes; ionic strength;
D O I
10.1016/S0022-0728(97)00380-X
中图分类号
O65 [分析化学];
学科分类号
070302 ; 081704 ;
摘要
Steady-state voltammetry for the reduction of labile complexes of lead, cadmium and mercury, in the absence of deliberately added supporting electrolyte and with different concentrations of supporting electrolyte, has been studied at mercury (lead and cadmium) and platinum disc (mercury) microelectrodes. The effects of ionic strength and nature of an inert electrolyte on the migrational component, which usually adds to diffusion in the mass transport in solutions with low electrolyte, have been examined. The results obtained have demonstrated that the ratio of limiting current at different concentrations of supporting electrolyte to diffusive limiting current I-lm/I-ld, depended not only on the charge of the free ion, but also on the amount of labile complexes formed between the metal ion with ligands which may arise from the counter-ion accompanying the metal in its starting salt, from small amounts of supporting electrolyte and from the autoprotolysis of water, i.e., OH-. Moreover, the I-lm/I-ld ratio is affected by the background electrolyte, which is almost unavoidable in water, and by the hydrolysis of the metal ion which yields protons. A comprehensive theoretical equation, based on already known treatments, has been also derived to predict the limiting current ratios in the presence of all the effects cited above. (C) 1997 Elsevier Science S.A.
引用
收藏
页码:153 / 161
页数:9
相关论文
共 30 条
[1]   MIGRATIONAL EFFECTS ON 2ND WAVES OF EE MECHANISMS UNDER STEADY-STATE OR QUASI-STEADY-STATE REGIMES [J].
AMATORE, C ;
BENTO, MF ;
MONTENEGRO, MI .
ANALYTICAL CHEMISTRY, 1995, 67 (17) :2800-2811
[2]   ELECTROCHEMICAL KINETICS AT MICROELECTRODES .5. MIGRATIONAL EFFECTS ON STEADY OR QUASI-STEADY-STATE VOLTAMMOGRAMS [J].
AMATORE, C ;
FOSSET, B ;
BARTELT, J ;
DEAKIN, MR ;
WIGHTMAN, RM .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1988, 256 (02) :255-268
[3]   A TRANSFORMATION FOR THE TREATMENT OF DIFFUSION AND MIGRATION - APPLICATION TO STATIONARY DISK AND HEMISPHERE ELECTRODES [J].
BAKER, DR ;
VERBRUGGE, MW ;
NEWMAN, J .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1991, 314 (1-2) :23-44
[4]   PERFORMANCE OF PLATINUM-BASED SPHERICAL MERCURY MICROELECTRODES IN CYCLIC VOLTAMMETRY AND STRIPPING ANALYSIS [J].
BALDO, MA ;
DANIELE, S ;
CORBETTA, M ;
MAZZOCCHIN, GA .
ELECTROANALYSIS, 1995, 7 (10) :980-986
[5]  
Bard A.J, 1980, Electrochemical methods: Fundamentals and applications
[6]  
Bockris J.O., 1970, Modern Electrochemistry, V1, DOI DOI 10.1007/978-1-4615-8600-5
[7]  
BOND AM, 1984, J ELECTROANAL CHEM, V172, P11, DOI 10.1016/0022-0728(84)80172-2
[8]   STEADY-STATE VOLTAMMETRY OF STRONG AND WEAK ACIDS WITH AND WITHOUT SUPPORTING ELECTROLYTE [J].
CISZKOWSKA, M ;
STOJEK, Z ;
MORRIS, SE ;
OSTERYOUNG, JG .
ANALYTICAL CHEMISTRY, 1992, 64 (20) :2372-2377
[9]   VOLTAMMETRY OF METALS AT MERCURY FILM MICROELECTRODES IN THE ABSENCE AND THE PRESENCE OF VARYING CONCENTRATIONS OF SUPPORTING ELECTROLYTE [J].
CISZKOWSKA, M ;
OSTERYOUNG, JG .
ANALYTICAL CHEMISTRY, 1995, 67 (06) :1125-1131
[10]   MICROELECTRODE STUDIES WITHOUT SUPPORTING ELECTROLYTE - MODEL AND EXPERIMENTAL COMPARISON FOR SINGLY AND MULTIPLY CHARGED IONS [J].
COOPER, JB ;
BOND, AM ;
OLDHAM, KB .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1992, 331 (1-2) :877-895