A Novel Thiocyanate-selective membrane Sensors based on Salicylaldehyde-o-Aminophenol Binuclear Copper (II) Complex as a Neutral Carrier

摘要

A new potentiometric thiocyanate-selective membrane sensor based on salicyladehyde-o-aminophenol binuclear copper (II) [Cu_2(II)-SOA] complex as a neutral carrier is reported, which displays a preferential potentiometric response to thiocyanate ion and an anti-Hofmeister selectivity sequence in the following order: SCN- > Sal- > ClO_4~- > I~- > NO_2~- > Br~- > Cl~-> NO_3~- > SO_3~(2-)> H_2PO_4~- > SO_4~(2-). The sensor exhibits a near-Nernstian potential over a wide linear range of 6.0×10~(-7) - 1.0×10~(-1) M with a detection limit of 2.0×10~(-7) M and a slope of –56.2 mV/decade in pH 4.0 of a phosphate buffer solution at 20°C.