The adsorption of a 1-pyrenebutanoic acid, succinimidyl ester (PSE) interacting with metallic armchair (n, n) carbon nanotubes (CNTs) (n= 3-13) was investigated by using a density-functional tight-binding method with an empirical van der Waals force correction. In this study of large systems involving weak interactions, our calculations showed that the pyrene ring of PSE could be spontaneously absorbed onto the CNTs surface through π-π stacking at the physisorption distances. Increasing of the CNTs diameter leads to a higher adsorption energy. After adsorption of PSE on its sidewall, the geometric and electronic structures of CNTs are basically undamaged. CNTs contribute to the main peak of the electron excitation procedure in the UV/vis spectrum, with a slight red shift after adsorption of PSE.
FAN WenJie & ZHANG RuiQin Centre of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, China
We report a novel nanotechnology-based approach for the highly efficient catalytic oxidation of phenols and their removal from wastewater.We use a nanocomplex made of multi-walled carbon nanotubes(MWNTs)and magnetic nanoparticles(MNPs).This nanocomplex retains the magnetic properties of individual MNPs and can be effectively separated under an external magnetic fi eld.More importantly,the formation of the nanocomplex enhances the intrinsic peroxidase-like activity of the MNPs that can catalyze the reduction of hydrogen peroxide(H2O2).Significantly,in the presence of H2O2,this nanocomplex catalyzes the oxidation of phenols with high effi ciency,generating insoluble polyaromatic products that can be readily separated from water.
Xiaolei ZuoCheng PengQing HuangShiping SongLihua WangDi LiChunhai Fan
