应用循环伏安和阻抗_电位法研究了硫脲(TU)对玻碳电极和镀镍玻碳电极上镍沉积过程的影响.结果表明,在玻碳电极上镍的电沉积呈现明显的电化学成核机理,而在镀镍玻碳电极上则无此特征.TU的存在虽阻碍了Ni晶核的形成,但却能加速晶粒的生长.
Effect of thiourea on nickel deposition at glassy carbon and nickel-deposited glass carbon electrodes was investigated with cyclic voltammograms and impetance-potential curves. It was found that the nucleation processes occurred at the glassy carbon electrode. However, this characteristics disappeared at the nicked-deposited glassy carbon electrode. It was suggested that the presence of thiourea hindered the nucleation processes, yet accelerated grain growth.Curves of impetance-potential could sensitively detect effect of thiourea on nickel depositon and reflect changes in rate-determining step with potential.
[1] Kwang_LungLin,Jia_WeiHwang.Effectofthioureaandleadacetateonthedepositionofelectrolessnickel[J].MaterialsChemistryandPhysics,2002,76:204~211.
[2] ZhaQuanxing(查全性).KineticofElectrodeProgress(电极过程动力学)[M].Beijing:ScientificPublication,Press,(科学出版社,北京),2002.131.
[3] SoutoRM,GonzalezS,ArevaloA.Ontheadsorptionofcadmium(II)ionsonaHMDEfromKF+thioureaaqueoussolutions[J].Electroanal.Chem.,1987,216:273~282
[4] SykutK,SabaJ,MarczewskaB.Daimata.TheinfluenceofthioureaontheelectroreductionofZn2+ionsinvarioussupportingelectrolytesinrespecttothecap_paireffect[J].Electroanal.Chem.,1984,178:295.