Electrodeposition of unsubstituted iron phthalocyanine nano-structure film in a functionalized ionic liquid and its electrocatalytic and electroanalysis applications

Abstract

We report a novel and facile electrodeposition method to fabricate a nano-structure film of the unsubstituted metal phthalocyanine on a glassy carbon electrode (GCE). In this electrodeposition system, unsubstituted iron(II) phthalocyanine (u-FePc) was chosen as the model complex of the unsubstituted metalphthalocyanine, and the ionic liquid 1-octyl-3-methylimidazolium trifluoroacetate was employed as the solvent and electrolyte, thus avoiding the use of additional costly supporting electrolyte. Excellent electrocatalytic performance of the u-FePc nano-structure film was first evaluated by electrocatalytic oxidation of ascorbic acid (AA). Compared with the bare GCE, the oxidation peak potential of AA at u-FePc/GCE shifted negatively about 264 mV, and the oxidation peak current increased about 1.8 times. Furthermore, the as-prepared film was employed for the investigation of luminol electrochemiluminescence (ECL) behavior in neutral solution, which showed excellent performance including under selected experimental conditions, the ECL intensity showing an acceptable linear relationship for luminol concentrations between 5 × 10⁻⁸ and 5 × 10⁻⁶ M, and a linear response to H₂O₂ over a wide concentration range, from 1.0 × 10⁻⁸ to 1.0 × 10⁻⁵ M in 3.0 μM luminol solution.