One-step encapsulation of functionalized EAQ and TBAQ molecules inside zeolite imidazolate framework-67 and their electrochemical characterizations

Abstract

Three anthraquinone functionalized zeolite imidazolate framework-67 (ZIF-67) hybrids, EAQ@ZIF-67-6 (ZE-6), EAQ@ZIF-67-10 (ZE-10) and TBAQ@ZIF-67-10 (ZT-10) (EAQ = 2-ethylanthraquinone and TBAQ = 2-tert-butylanthraquinone), have been synthesized by one-pot strategy. The successful encapsulation of guests in hybrids has been characterized and confirmed by PXRD, SEM, FT-IR, UV-vis and N2 adsorption. The loading amounts of 11.87 wt% EAQ for ZE-6, 23.11% EAQ for ZE-10, and 23.92% TBAQ for ZT-10 were determined by UV-vis absorption spectroscopy. Their detailed electrochemical studies were performed by using cyclic voltammetry at hybrids modified glassy carbon electrode (GCE) and carbon paste electrode (CPE). The cyclic voltammogram of each hybrid exhibits three pairs of separated redox peaks owing to both electrochemical properties of AQs and ZIF-67. Moreover, the ZE-10 functionalized GCE and CPE have a detection limit of 0.05 mM for H2O2 reduction. These hybrids were the first attempt of electrochemical active molecules embedded into a porous conductive framework.