Assembly of polyoxometalate-templated metal-organic framework with effective peroxidase-like catalytic activity

A new polyoxometalate (POM)-templated 3-D copper(II)-triazole framework [Cu-10(trz)(10)(OH)(6)(Cl)(4)][H3PW12O40]center dot 2H(2)O (trz = 1,2,3-triazole) has been synthesized and characterized by single crystal X-ray diffraction and other routine methods. The 3-D POM/copper(II)-triazole hybrid framework with a 1-D channel possesses a pcu topology under the template of bulk Keggin-type phosphotungstate. As a new kind of peroxidase mimetic, the new compound effectively catalyzed oxidation of 3,3 ',5,5 '-tetramethylbenzidine (TMB) in the presence of H2O2. The electrostatic interactions and hydrogen bonds/pi-pi stacking interactions among TMB, trz, and phosphotungstate are responsible for the enhancement of peroxidase-like activity. In addition, application for colorimetric sensing of H2O2 is also explored; the new compound exhibits a wide linear range (1-80 mu M), low detection limit (0.21 mu M), and fast response (2 min). [GRAPHICS] .