Electrically Conducting Nanoporous Membrane Untitled
EMSL Project ID
48527
Abstract
Using carbon nanotubes (CNTs) we have assembled a nanoporous membrane that has electrically conducting CNTs as porous templates. This is a unique membrane material with many important applications. Because the CNTs are electrically conductive, this material can function as an electrode with significant benefits for trace analysis. The array of conductive sites imbedded in a nonconductive matrix gives substantially improved limits of detection for the electrochemical determination of pollutants such as heavy metals (mercury, lead, cadmium) and polycyclic aromatic hydrocarbons that are of concern at some Superfund sites. Other applications take advantage of the nanopores of the CNTS that traverse the membrane. The nanosize pore dimensions make the membrane ideal for water desalination in which water molecules can pass through the pores, but hydrated salt ions cannot. The main advantage for desalination is that H2O molecules can reach ballistic speeds within the pores due to the hydrophobic nature of the inner CNT walls. By varying the pore geometry and dimensions, and with additional chemical functionalization of the CNT open ends, the membrane could be used for gas or protein purification among other applications. CNT nanopores could also serve as an ion selective membrane for a highly sensitive detector for ions that can be employed to study soil contamination, perhaps even aerosol detection in the environment. The proposed research entails imaging the cross section of the CNTs used as the porous template. Determining the nature of these pores, their geometrical shape and size, the concentration of CNTs within the membrane, as well as imaging of the concentric CNT walls constitute our main objectives. The proposed studies require a high level of expertise in microtoming of the material into nanothin membranes for TEM measurements down the axis of the CNTs. Alternatively, the use of an ion-beam to mill the nanoporous material down to approximately 10 nm thickness can be employed to provide transparency to the electron beam samples for successful imaging by HRTEM or cryo-TEM.
Timing is critical for us in order to obtain results for a publication that we can use for Preliminary Results in an NSF proposal to the Sensors and Sensing Systems directorate with a deadline of September 1, 2014.
Project Details
Project type
Limited Scope
Start Date
2014-10-23
End Date
2014-11-24
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members