Trapped in the coordination sphere: nitrate ion transfer driven by the cerium(iii/iv) redox couple. Issue 45 (7th November 2016)

• Record Type: Journal Article
• Authors: Ellis, Ross J.; Bera, Mrinal K.; Reinhart, Benjamin; Antonio, Mark R.
• Is Part Of: Physical chemistry chemical physics. Volume 18:Issue 45(2016)
• Page Start: 31254
• Page End: 31259
• Publication Date: 2016-11-07
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c6cp06528g
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : The electrochemical transfer of nitrate anions between oil and water phases—driven by the reduction and oxidation of cerium coordination complexes in oil phases—provides a new entry into chemical separations where an electrode potential tunes solute transfer between phases by 'trapping' the migrating anion on the cerium cation. Abstract : Redox-driven ion transfer between phases underpins many biological and technological processes, including industrial separation of ions. Here we investigate the electrochemical transfer of nitrate anions between oil and water phases, driven by the reduction and oxidation of cerium coordination complexes in oil phases. We find that the coordination environment around the cerium cation has a pronounced impact on the overall redox potential, particularly with regard to the number of coordinated nitrate anions. Our results suggest a new fundamental mechanism for tuning ion transfer between phases; by 'trapping' the migrating ion inside the coordination sphere of a redox-active complex. This presents a new route for controlling anion transfer in electrochemically-driven separation applications.