Membranes with well-controlled nanoscale pores have enormous potential for applications as diverse as breathable protective membranes for soldiers and medical providers, water purification, and “green” power generation. Working with collaborators Dr. Francesco Fornaserio (Lawrence Livermore National Laboratory), Prof, Ken Carter (U Mass), Prof. Tim Swager (MIT), and Dr. Bob Praino (Chasm, Inc.), we are devising scalable, solution-based approaches for fabricating protective membranes with aligned carbon nanotubes as through pores. The same approach is also being applied to develop other membranes for green energy (working with collaborator Sangil Kim, UI Chicago). Our goal is not only to develop and characterize the novel nanomembranes, but also the manufacturing processes that will enable them to fabricated in industrially relevant quantities.
Nanomaterials can vary widely in properties, even within the same batch. For electronic nanomaterials, the properties may vary for either extrinsic reasons, depending for example on variability in processing conditions, or for intrinsic reasons such as a discrete number of charge carriers. We are devising highly efficient, solution-based methods for measuring the electrical properties of low-dimensional nanomaterials. Working with Prof. Michael Filler (Georgia Tech), and Prof. Len Feldman (Rutgers), we are using these new characterization tools to understand the statistical variability of nanowires and nanotubes, and ultimately to design syntheses, systems, and manufacturing processes to enable robust, high-performance nanomaterials and devices.
Furthermore, to fully realize the enormous potential of many nanomaterials, fast, automated methods are needed to manipulate and position them at desired locations. We are working with Prof. Jingang Yi (Rutgers) to develop electric-field-based methods for the automated positioning of liquid-suspended nanowires at arbitrary target locations with a simple, generic set of electrodes. This work will help provide a foundation for scalable, automated methods for positioning nanomaterials and building nanodevices.
Through precise adjustments of electric or magnetic fields, nanoparticles and nanotubes in liquid suspension can be directed to rotate into alignment and/or self-assemble into chains. This controlled forcing by external fields offers a simple and precise means to study fundamental hydrodynamics and electromechanics at the nanoscale. It also allows us to study the connection between field-induced micro-structure and effective thermophysical properties, and to develop smart materials with controllable properties. We have been studying novel composites and suspensions with tunable and anisotropic rheology, electrical and thermal conductivities, and acoustical properties.
Electroporation is the transient, electrically induced transport of foreign molecules into cells. It is widely used in research and clinical applications for gene insertion and protein or drug delivery. However, electroporation protocols must typically be empirically derived for the delivery of specific molecules to specific cell types. Working with industrial collaborators and colleagues Hao Lin, David Shreiber, and Jeff_ Zahn at Rutgers, we are developing a basic understanding of electroporation, and the technology to realize efficient electroporation to both individual cells and tissue via “smart” electroporators with real-time monitoring and feedback control.
