A multifunctional Zr(iv)-based metal-organic framework for highly efficient elimination of Cr(vi) from the aqueous phase

摘要

A highly stable luminescent Zr(iv)-MOF, [Zr6O4(OH)(8)(H2O)(4)(TCPP)(4)]center dot 9DMF center dot 3.5H(2)O (JLU-MOF60, H4TCPP = 2,3,5,6-tetrakis(4-carboxyphenyl)pyrazine, DMF = N,N-dimethylformamide) was successfully prepared. JLU-MOF60 with the AIE effect and high porosity consists of 8-c Zr-6 clusters and 4-c ligands with an sqc topology. Interestingly, it exhibits remarkable chemical stability in water over extensive pH values varying from 0 to 11. Due to its outstanding water stability and Zr-bonded hydroxides in the framework, JLU-MOF60 shows a high capture capability (149 mg g(-1)) and rapid adsorption rate (38 mg g(-1) min(-1)) for Cr2O72- in water. Moreover, benefiting from the AIE effect of the H4TCPP ligand, JLU-MOF60 can not only sensitively and selectively detect Cr2O72-, but also effectively photo-reduce Cr(vi) to Cr(iii) in the aqueous phase. It is worth mentioning that the K-SV value of JLU-MOF60 for detecting Cr2O72- is as high as 5.91 x 10(4) M-1, and the detection limit is as low as 0.38 mu M. Simultaneously, the kappa value of the photocatalytic reaction can reach up to 0.058 min(-1). Accordingly, JLU-MOF60 can be regarded as a multifunctional material to efficiently eliminate Cr2O72- from the aqueous phase.