NEARLY ALL NANOMATERIAL APPLICATIONS REQUIRE an interface with other materials, including, for example, polymers in composites, electrodes in devices, pharmaceuticals in drug delivery, body fluids and cells in bioimaging and biosensors, or analytes in chemical sensors. Our group focuses on developing a fundamental understanding of interfaces in nanoscale systems, which can have far-reaching implications to various fields of nanotechnology. The goal is to manipulate interfaces to dictate the nanostructures that are fabricated and to control reactions and transport at the surface of the nanostructures. Once these interfaces can be controlled and manipulated, it is possible to fabricate nanomaterials with novel functionality, improving their integration and performance in several applications.

MANIPULATING INTERFACES The ultimate objective is to create new functionality by manipulating the interface. The manipulation of nanoscale interfaces can alter the wettability, interaction of nanomaterials with matrices, and their stability to environmental effects. We aim to control these interfaces to alter the dispersion and sensing properties of the nanoparticles. These factors also limit the organization and dimensions of nanostructures that are fabricated. For example, we have exploited the natural sensing capabilities of single walled carbon nanotubes (SWCNTs) to help us characterize the localized environment surrounding them. The ability to characterize the surface of SWCNTs has enabled the development of processes to alter the surfactant structure surrounding the nanotube, providing more stable suspensions, better fluorescence intensities, selective adsorption onto surfaces, and reduced toxicity.

CONTROLLING REACTIONS AND TRANSPORT AT SURFACES Nanotechnology offers significant promise to improving the performance of solar cells, batteries, and supercapacitors because of the large surface area and unique properties of nanomaterials. However, designing these devices requires exceptional control of the chemical and electronic processes that occur at interfaces. Since many of the atoms in nanostructures exist on the surface, their reaction and transport properties depend strongly on the interface. Our group develops processes that control reactions and transport at the surface to synthesize porous materials suitable for gas phase separations. These nanomaterial interfaces can also be used to help control biological function or accessibility, enhance the collection of photons, improve charge transport, yield better heat transfer, and generate more plasma.

Education

Ph.D., University of Texas at Austin, 2001
B.S., University of Cincinnati, 1996

Awards & Distinctions

• Charles A. Stokes Endowed Professorship in Chemical Engineering, 2021-2024
• Dow Chemical Company Foundation Professorship in Chemical Engineering, 2018
• University of Florida Term Professorship, 2017 – 2020
• University of Florida Graduate School Doctoral Mentoring Award, 2017
• College of Engineering Doctoral Mentoring Award, 2017
• Chemical Engineering Faculty Excellence in Service Award, 2016

selected Publications

• “Boiling and quenching heat transfer advancement by nanoscale surface modification,” H. Hu, C. Xu, Y. Zhao, K.J. Ziegler, and J.N. Chung. Sci. Rep., 7, 6117 (2017). [doi: 10.1038/s41598-017-06050-0]
• “Controlling the geometries of Si nanowires through tunable nanosphere lithography,” L. Li, Y. Fang, C. Xu, Y. Zhao, K. Wu, C. Limburg, P. Jiang, and K.J. Ziegler. ACS Appl. Mater. & Interfaces, 9, 7368-7375 (2017). [doi: 10.1021/acsami.6b09959]
• “Selective desorption of high-purity (6,5) SWCNTs from hydrogels through surfactant modulation,” Y. Zhao, J.G. Clar, L. Li, J. Xu, T. Yuan, J.-C.J. Bonzongo, and K.J. Ziegler. Chem. Commun., 52, 2928-2931 (2016). [doi: 10.1039/c5cc08530f]
• “Relationship between single-file diffusion of mixed and pure gases in dipeptide nanochannels by high field diffusion NMR,” A. Dutta, P. Sekar, M. Dvoyashkin, C.R. Bowers, K.J. Ziegler, and S. Vasenkov. Chem. Commun., 51, 13346-13349 (2015). [doi: 10.1039/c5cc04960a]
• “Improving performance via blocking layers in dye-sensitized solar cells based on nanowire photoanodes,” L. Li, C. Xu, Y. Zhao, S. Chen, and K.J. Ziegler. ACS Appl. Mater. & Interfaces, 7, 12824-12831 (2015). [doi: 10.1021/acsami.5b02041]
• “Interactive forces between SDS-suspended single-wall carbon nanotubes and agarose gels,” J.G. Clar, C.A. Silvera Batista, S. Youn, J.-C.J. Bonzongo, and K.J. Ziegler. J. Am. Chem. Soc., 135, 17758-17767 (2013). [doi: 10.1021/ja4052526]
• “Swelling the micelle core surrounding single-walled carbon nanotubes with water-immiscible volatile organic solvents,” R.K. Wang, W.-C. Chen, D.K. Campos, and K.J. Ziegler. J. Am. Chem. Soc., 130, 16330-16337 (2008). [doi: 10.1021/ja806586v]