高稳定性普鲁士蓝修饰电极的制备和研究

采用恒电流电解方法,使用FeCl_3-K_3Fe(CN)_6和Fe~(?)L_(?) -K_3Fe(CN)_6(L,邻菲绕啉,EDTA,5-磺基水杨酸等)两体系,在玻碳和铂基体上均制得高稳定性普鲁士蓝膜。用循环伏安法在lmol·dm~(-3)KCl(pH4)溶液中,重点地在0.6--1.1V(vs.Ag/AgCl)区间研究了膜的电化学稳定性。在玻碳基体上FeCl_3,-K_3Fe(CN)_6和Pe~(?)·L_(?) -K_3Fe(CN)_6体系电积膜分别可经受10~(?)周和2×10~(?)周扫描。在铂基体上则可分别经受2×10~(?)和7×10~(?)周扫描。红外和X-射线衍射证明两体系制得的膜均为普鲁士蓝膜,稳定性的明显差异是由于普鲁士蓝晶粒度的不同和在基体表面的相对取向不同引起的。对影响膜的稳定性的因素作了较系统的研究。

PREPARATION AND BEHAVIOUR OF HIGHER STABI-LITY PRUSSIAN BLUE MODIFIED ELECTRODE

The higher stability of prussian blue modified elecctrodes have been prepared by constant current electrolytic deposition method. In electrolytic preparation, the mixed ligand complex systems (FeLx - K3Fe(CN)6)(L: phenathroline, EDTA, 5-sulfosalicylic acid or tartratic acid respectively) were used instead of traditional FeCl3 - K3Fe(CN)6 system. The more stable Prussian blue modified carbon electrodes were obtained from above mixed ligand complex solutions than that from FeCl3 - K3Fe(CN)6 system. More stable Prussian blue modified carbon electrodes which can undergo over two thousand cycles of potential sweep between 0.6V and 1:1V (vs. Ag/ AgCl) have been prepared. The relation between the preparation conditions, the stabilities and the voltammetric behaviour of the modified electrodes have been studied systemmatically.