7,7 ';,8,8 ';-Tetracyanoquinodimethane as a redox probe for studying cation transfer across the water/2-nitrophenyl octyl ether interface at three-phase junctions supported by carbon ink screen-printed electrodes

作者：Wu Suozhu; Su Bin^*

来源：Journal of Electroanalytical Chemistry, 2011, 656(1-2): 237-242.

DOI：10.1016/j.jelechem.2010.11.004

• Cation transfer
• Three-phase junctions
• Carbon ink screen-printed electrode
• 7,7 '
• ,8,8 '
• -Tetracyanoquinodimethane
• Lipophilic cation

The transfer of alkylammonium cations across the water/2-nitrophenyl octyl ether (NPOE) interface was studied at the three-phase junctions supported by a carbon ink screen-printed electrode (SPE) using cyclic and square-wave voltammetry. A microliter droplet of NPOE containing 7,7';,8,8';-tetracyanoquinodimethane (TCNQ) was immobilized on the surface of the SPE and was immersed in aqueous solutions containing various alkylammonium salts. A plot of the half-wave transfer potential versus the logarithm of the cation concentration exhibits a close to Nernst slope. Moreover, a plot of the half-wave transfer potentials against the formal transfer potentials of alkylammonium cations yielded a slope close to unity. All these experimental facts suggest that the reduction of TCNQ at the SPE/NPOE interface is accompanied by a simultaneous cation transfer across the NPOE/water interface to preserve the electroneutrality of the organic microdroplet, namely the overall process corresponds to a cation-coupled electron transfer reaction. Finally, this approach allowed measuring the formal transfer potential of highly lipophilic cation, such as bis(triphenylphosphoranylidene)ammonium.

• 出版日期2011-6-15
• 单位浙江大学