Student News

Third IC4N 2011

3rd International Conference from NANOPARTICLES & NANOMATERIALS to NANODEVICES & NANOSYSTEMS
June 26-29, 2011
Crete Island, Greece

Silver-Carbon Nanotube composite for wastewater treatment

R. Roy, N. Burnham, J. Liang

Abstract: Nanoparticles are much more reactive than their conventional macro-scale counterparts, due in part to their greater surface area per weight.  The optimization of a silver-CNT composite with good adhesion between the nanoparticles and the nanotube substrate is expected to provide an effective means at treating industrial wastewater in a simple and cost effective manner.  Preliminary results exhibit strong support of this investigation.

Silver has been proven to effectively kill waterborne viruses, parasites, bacteria, protozoan and other microorganisms.  Not only can it clean wastewater without leaving any residual presence, but it can also greatly benefit in improving aesthetics.  In particular, it can eradicate bacteria, such as actinomycetes, that cause foul odors and taste, which conventional treatment methods usually do not consider. 

Carbon, traditionally used for water treatment, is used to serve as a medium to support silver particles. The objectives in this study is fourfold: adhere silver nanoparticles onto the CNT with control over dispersion and size, test its effectiveness to treat organic and biological matter in wastewater, compare this optimized nanocomposite with conventional carbon filter and chemical methods, and examine the cost savings associated with this method of treatment.

A bottom-up chemical reduction approach is used to produce silver nanoparticles without aggregation at high yield and low-cost.  By controlling various synthesis parameters such as concentration, pH, and additives, silver nanoparticles can be created at the desired diameter. Scanning and Transmission Electron Microscopy (SEM & TEM) are employed to characterize the particle size and distribution.  Lateral Force Microscopy and mechanical methods are utilized to test adhesion forces of the silver particles onto the carbon nanotubes microscopically as well as macroscopically.

Preliminary results show an average stable particle size of 8nm of silver on the CNT’s.  Adhesion properties have also been improved by specially treating the CNT surfaces. 

Through further adjustment of the synthesis conditions, Ag nanoparticles with desirable morphology are tested in the treatment of industrial wastewater.  Optimizing this nanocomposite is the first step in creating a more complex and more effective nanocomposite that can treat a broader range of containments.

 Download the poster (pdf)

July 13, 2011