Zirconium metal-organic framework supported highly-dispersed nanosized BiVO4for enhanced visible-light photocatalytic applications

BACKGROUND As a super stable zirconium based metal-organic framework, Zr6(OH)4(C8H6O4)6 (UiO-66) is considered a competitive candidate to conjugate with photocatalyst to enhance photocatalytic activity. In this study, highly dispersed bismuth vanadate (BiVO4) nanoparticles grown in situ upon the surfaces of UiO-66 were synthesized through a simple method, and the photocatalytic activities were investigated by measuring the degradation of rhodamine B (RhB) under visible light irradiation. RESULTS The results show that UiO-66@BiVO4 composite with Bi:Zr molar ratio of (1:1) was the optimum hybrid and exhibited much higher photocatalytic activities than that of pure BiVO4. Furthermore, the photocatalyitc mechanism of RhB degradation by UiO-66@BiVO4 was also investigated, the photodegradation of RhB was mainly caused by the super oxide ions (·O2−). The lone pair electrons of surface group –OH and –COOH of UiO-66 attract the photogenerated holes (h+), which effectively prevent the recombination of electrons and holes. CONCLUSIONS The enhanced separation of photogenerated electron–hole pairs through interfaces between BiVO4 and UiO-66 led to improvement of the photocatalytic activity. The study showed a degradation mechanism for RhB wasterwater treatment. © 2016 Society of Chemical Industry