Electrochemical Behavior of Bis(2,2'-Bipyridyl) Copper(II)-Sodium Dodecyl Sulfate Solution in the Presence of $MgCl_2$

염화마그네슘이 있을 때 비스(2,2'-비피리딜)구리(II)-도데실황산나트륨 용액의 전기화학적 거동

  • Ko, Young Chun (Department of Chemistry, Chonnam National University) ;
  • Chung, Keun Ho (Department of Chemistry Education, Chonnam National University)
  • Received : 1996.10.21
  • Published : 1997.04.25

Abstract

Electrochemical behavior of 1.0mM bis(2,2'-bipyridyl)copper( II )(${Cu(bpy)_2}^{2+}$) in 100mM NaCl+27mM $MgCl_2$ solution with and without sodium dodecyl sulfate(SDS) is investigated. In the presence of SDS, $E_{pa}$ and $E_{1/2}$ of ${Cu(bpy)_2}^{2+/1+}$ shifts to the positive direction compared to the SDS free. Teh intersection of two lines on ${\Delta}E_p$ vs. -log[SDS] plot for 1.0mM $Cu(bpy)_2(NO_3)_2$ in 100mM NaCl+27mM $MgCl_2$ solution is a critical micelle concentration(CMC). Reduced form ${Cu(bpy)_2}^{1+}$ in the presence of $MgCl_2$ is more easily associated to dodecyl sulfate anion($DS^-$) than oxidized ${Cu(bpy)_2}^{2+}$. As the ionic strength is increased by the addition of multiply charged cations($MgCl_2$), the double layer becomes more compact and micelle formation is more difficult.