Sustainable synthesis of HKUST-1 and its composite by biocompatible ionic liquid for enhancing visible-light photocatalytic performance

Cyhalothrin is lethally toxic to aquatic organisms and has caused adverse effects in the hydrosphere. It is urgent to develop efficient and sustainable material for its removal. High-quality HKUST-1 was rapidly synthesized by cholinium ionic liquids (ILs) in water at room temperature. Yields of HKUST-1 showed obviously positive correlation with Hammett values of ILs. When applying CuCl2 as a copper salt, the yield of products was reached up to 95.5%, which was much higher than that of reported research. The reaction could be readily scalable with high space-time yield (242512 kg m(-3) d(-1)). Additionally, ZrO2@HKUST-1 composite was successfully synthesized through a sol-gel method without complicated heat treatment. The whole process eliminates the use of environmentally unfriendly solvents/amines and enables the production of material at a reasonable cost. The obtained HKUST-1 and ZrO2@HKUST-1 possessed large pore volume (0.88-0.95 cm(3) g(-1)) and high surface area (1152-1484 m(2) g-1). The composite material was used for the adsorption/degradation of cyhalothrin and showed superior photo catalytic activity under moderate visible light, as compared to pure ZrO2, HKUST-1 and commercial TiO2 samples. ZrO2@HKUST-1 displayed the high cyhalothrin adsorption capacity of 333 mg g(-1) through pi-pi stacking, which facilitated more target molecules to contact the composite in a short time. ZrO2 incorporating with HKUST-1 protected ZrO2 nanoparticles from rapid agglomeration, thus narrowed the band gap of the composite. Moreover, the formation of a junction between HKUST-1 and ZrO2 effectively reduced the recombination of photoinduced carriers in composite. Therefore, the novel ZrO2@HKUST-1 composite can be used as a sustainable efficient heterogeneous photocatalyst for the removal of organic pollutant. (C) 2018 Elsevier Ltd. All rights reserved.