Metal Nanoparticles on Hierarchical Carbon Structures: New Architecture for Robust Water Purifiers

S.M. Mukhopadhyay, A.K. Karumuri, H. Vijwani
Wright State University, US

Keywords: nanotubes, nanoparicles, antibacterial, dechlorination, surface chemistry

Summary:

A new architecture for robustand powerful water purification media has been investigated. It consists of carbon nanotubes (CNT) attached to porous microcellular substrates. This is similar to several elegant and multifunctional designs seen in nature where dendrites and capillaries are attached to larger organs increasing their surface area. For this application, palladium and silver nanoparticles are attached to these surfaces for catalytic and anti-microbial activities. Palladium is a powerful catalyst for several reactions. In this study, the kinetics of carbon tetrachloride removal form water using Pd-activated material has been measured, and found to be very high. Silver nanoparticles are useful as antimicrobial agents and as plasmonic sensors. The effectiveness of these structures to remove E-coli from water has been tested, and the rates compared to currently available nano-silver materials. Both nano-particles were seen to be strongly attached to the nanotubes which were in turn strongly attached to the substrate. Durability tests indicate that failure occurs by delamination of graphite inside the substrate, rather than removal of individual CNT or nanoparticles from CNT. This observation bodes well for future use of this architecture in robust and efficient water purification devices.