电化学还原脱氯用GC负载Pd-Ni电极的制备及表征

Preparation and characterization of glassy carbon electrode modified by composite palladium-nickel film used in electrochemical reductive dechlorination

通过电沉积法在玻碳板(GC)电极上负载钯镍双金属颗粒,并利用正交实验对其进行循环伏安(CV)研究,得到Pd-Ni/GC电极的最佳制备条件为:Ni2+=8.5mmol.L-1,Pd2+=3mmol.L-1,pH=7.0,Jk=15mA.cm-2,T=30min。可以在-500mV(以Hg/Hg2SO4为参比电极)左右获得-24.83mA的氢吸附峰。用聚吡咯(PPy)修饰GC制备Pd-Ni/PPy/GC电极,CV结果表明,Pd-Ni/PPy/GC电极具有比Pd-Ni/GC电极更大的氢吸附峰值,可以在-500mV(以Hg/Hg2SO4为参比电极)左右获得-32.33mA的氢吸附峰。扫描电镜(SEM)分析表明,聚吡咯的修饰明显改变了Pd-Ni颗粒的沉积形态,使其沉积粒径更小,分散度更高。

The electrochemical deposition behavior of Pd-Ni bimetal on glassy carbon （GC） electrode was studied by means of cyclic voltammetry （CV） based on orthogonal experiments. The optimum preparation conditions of Pd Ni/GC electrode were Ni^2＋ =8.5 mmol · L^-1, Pd^2＋ =3 mmol · L^-1, pH=7. 0, Jk =15 mA · cm^-2, and T= 30 min. The hydrogen adsorption peak on Pd Ni/GC electrode of - 24. 83 mA was obtained at about -500 mV （vs Hg/Hg2SO4）. Pd-Ni/PPy/GC electrode modified by polypyrrole film was prepared. CV results revealed that the hydrogen adsorption peak of --32.33 mA was obtained at about --500 mV （vs Hg/Hg2SO4）, which was larger than that on Pd Ni/GC electrode. Scanning electron microscope （SEM） images revealed that PPy film changed the deposition configuration of Pd-Ni particles evidently. The diameters of Pd-Ni microparticles were smaller and the dispersion degree was hitcher.