Mechanochemical synthesis of Cu-BTC@GO with enhanced water stability and toluene adsorption capacity

A solvent-free mechanochemical method is proposed to quickly synthesize composites (Cu-BTC@GO) of Cu-BTC and graphite oxide within 30 min. The resulting composites were characterized by N-2 adsorption, PXRD, SEM, FT-IR and TG. Its water-stability and adsorption properties toward toluene vapor were examined. Results showed that mechanochemical method can quickly prepare the composites Cu-BTC@GOs by mechanical grinding without solvent. The resulting Cu-BTC@GOs had higher BET surface area and pore volume than the parent Cu-BTC, of which the composite Cu-BTC@GO-5 possessed the highest surface area of 1362.7 m(2)/g and total pore volume of 0.87 cm(3)/g and its toluene uptake up to 9.1 mmol/g at 298 K, having an increase of 47% in comparison with Cu-BTC, much higher than those of the conventional activated carbons and zeolites. More interestingly, its water-stability had greatly been enhanced. After soaked in water for 10 h, Cu-BTC@GO-5 still remained its structure and porosity and its BET surface area remained 1205 m(2)/g. It may be ascribed to the coordination between the oxygen groups in the GO and Cu2+ mental center in Cu-BTC. In contrast, the water-soaked Cu-BTC completely lost its structure and porosity. Its surface area decreased sharply to 20.7 m(2)/g from its initial surface area of 1188.3 m(2)/g, having a decrease of 98.2%. The application of mechanochemical synthesis to prepare composites Cu-BTC@GOs is an effective strategy for enhancing adsorption property and water-stability of Cu-BTC. The excellent water stability and high adsorption capacity of toluene would make Cu-BTC@GOs a promising candidate for practical applications in field of VOCs adsorption. (C) 2016 Elsevier B.V. All rights reserved.