A robust polyoxometalate-templated four-fold interpenetrating metal-organic framework showing efficient organic dye photodegradation in various pH aqueous solutions

A Keggin-type polyoxometalate (POM)-templated metal-organic framework, [Cd(TTPB-4) (DMF)(3)](4)[PMo12O40](2)[HPMo12O40]center dot 6DMF center dot 4H(2)O (1), based on a newly designed linker of TTPB-4 [TTPB-4 = 1,3,5-tris(4-(4H-1,2,4-triazol-4-yl) phenyl) benzene], has been hydrothermally synthesized and characterized using IR, XRD, TGA, UV-Vis and photoluminescence spectra. Single-crystal X-ray crystallography reveals that 1 represents a unique POM-templated four-fold interpenetrated 3-D coordination network. The POM-templated MOF of 1 exhibits strong chemical stability that can withstand aqueous solutions of various pH-values (2-10). Particularly, 1 possesses excellent photodegradation activity and recyclability towards the organic dyes of Crystal Violet (CV) and Basic Red 2 in aqueous solutions with different pH values.