Filliing of carbon nano-tubes with nano active metal species and their studies on the physico-chemical behaviors

Abstract

Nanomaterials exhibit interesting physical properties distinct from both the molecular and broad scales, presenting new opportunities for physico-chemical as well as biomedical researches and applications in various areas of chemistry, biology and medicine. The unique chemical, physical and mechanical properties of CNTs have stimulated extensive investigation since their discovery in early1990s by Iijima.The present reserch interest focuses on the development of simple and cost effective way for the synthesis of CNTs and proposes the new idea of bulk chemical method. Filling hollow CNTs with chosen materials opens new possibilities of generating nearly one dimensional nanostrutures. One simple approach to fill the hollow cavity of CNTs is continuous boiling of the mixture suspension of CNTs and other nanoactive species at 100 oC for several hours. For the filling purposes four nanoactive metal species (NiO, Ni, Mn3O4, MnO2) were prepared using established conventional methods. NiO nanoparticles were prepared using precipitation method. Ni nanoparticles were prepared by control reduction of NiO nanoparticles. Mn3O4 nanoparticles were prepared from hydrolysis of manganese (ll) acetate. MnO2 were prepared by treating manganese (ll) acetate with potassium permanganate. Nanoparticles increase chemical activity due to crystallographic surface structure with their large surface to volume ratio. This has promoted research to check the antibacterial activity of the prepared Mn3O4 nanoparticles of definite size. Researches have been reported on CNT-based drug delivery. CNT itself don’t have any antibacterial activity and can easily release the carring drugs to the target places at definite chemical environments. Adsorption of methylene blue dyes on the surface of NiO loaded CNTs represents an important and intensively studied phenomenon. From the adsorption studies it was observed that the rate constant(k2) of CNTs and NiO is 1.82×10-5 gμg-1min-1 and 1.27×10-4 gμg-1min-1. Here it should be clear that the adsorption capacity is higher for CNTs than NiO nanoparticles but it is comperatively time cosuming. The rate constant(k2) of NiO loaded CNTs is 6.62×10-5 gμg-1min-1. The adsorption rate of NiO filled CNTs are slightly higher than CNTs. This is because of the total increasd surface area of NiO nanoparticles loaded CNTs. This excess surface area as well as the overall functionalization did impact on the rate of adsorption.