关键词: 硬脂酸钠, 蓖麻油/水界面, 自组装膜, 循环伏安, 石墨粉-环氧树脂固态电极

Abstract: The self assembly membrane(SAM)formation kinetics of sodium stearate at castor oil/water interface was studied by cyclic voltammetrry.At caster oil coated graphite-epoxy solid electrode surface,the SAM grows according to the Gaussian growth function with a rate constant of km=0.0006292(0.0000294)s-1,and maximum particle size at t0=3127s.The SAM of sodium stearate controls the growth and particle size of the deposited copper nano particles well,and forms a composite membrane of the SAM and copper nano particle.The growth mechanism of copper particle at oiled electrode or SAM modified oiled electrode is spherical growth,while it is the semi-spherical growth at bared graphite-epoxy solid phase electrode.Compared with castor oil coated electrode,the deposited copper particles show the stronger interaction to graphite-epoxy solid phase electrode surface with the free energy change of ΔG0 = 3.86 kJ/mol and a weaker interaction to the SAM of sodium stearate with the free energy change of ΔG0=-2.412 kJ/mol.

Key words: sodium stearate, castor oil/water interface, self assembly membrane, graphite-epoxy solid phase electrode