Our research is dedicated to understanding the properties of materials at the nanoscale. Some of our current research themes include:
Synthesis and Characterization of Novel Materials: Prof. Rao's Lab at Clemson University has been highly succesful in synthesis of Nanomaterials. Some breakthrough technologies such as the continuous production of aligned MWNTs, Low-melting metal oxide nanowires etc. were discovered at Clemson. Currently, our focus is on synthesis of doped single-, bi- and few-layer graphene, Graphene quantum dots (GQDs), Bucky Aerogel (BAG), Helically coiled nanotubes and nanowires etc. We explore the fundamental physics in nanostructured systems using a wide range of characterization techniques such as Raman scattering, infrared, UV-visible, fluorescence, non-linear optical spectroscopy, harmonic detection of resonance method (HDR), atomic force microscopy, electron microscopy, and electrical transport measurements. Some of our recent pulications in this area are below. Click on the title to open it in a new tab.
Raman Spectroscopy of Folded and Scrolled Graphene Link
Electron Phonon Renormalization in Doped Graphene Link
Effects of Disorder on the Optical Properties of CVD grown Polycrystalline Graphene Link
Understanding Nano-bio interactions: The global market for nanomaterials based products was forecasted to 100 billion dollars per annum for 2011–2015. Extensive manufacturing and the use of nanomaterials have raised concerns regarding their impact on biological response in living organisms, and the environment at large. The fundamental properties of nanomaterials exhibit a complex dependence upon several factors such as their morphology, size, defects, chemical stability, etc. Therefore, it is exceedingly difficult to correlate their biological response with its intricate physicochemical properties. For example, varying toxic response may ensue due to different methods of ENM preparation, dissimilar impurities and defects. Hence, an appropriate analysis of the observed biological response or cytotoxicity demands a need for excellent in-vivo and in-vitro characterization of nanomaterial properties. Our lab at Clemson employs spectroscopic tools to characterize and understand fundamental properties of nanoparticle-protein corona, nanotoxicity etc. Apart from the fundamental studies, Rao's Lab designs novel materials such as graphene for biomedical devices and sensors.
Multi-Walled Carbon Nanotube Instillation Impairs Pulmonary Function in C57BL/6 Mice Link
Evidences for Charge Transfer-Induced Conformational Changes in Carbon nanotube Protein Corona (Submitted)
Engineered Nanocomposites for Efficient Energy Storage: An upsurge in the global energy demand warrants a “re-exploration” for efficient electrochemical energy storage mechanisms, due to (i) the rapid dwindling of traditional energy reserves (e.g. fossil fuels, natural gas); (ii) the failure of current battery storage technologies (regardless of the origin of energy generation, viz., solar, wind) to meet industrial demands for combined power and energy densities; and (iii) the great promise of advanced nanostructured materials for improving charge storage mechanisms. Capacitors can deliver high-power density while batteries can deliver high-energy density. Supercapacitors, expected to bridge the gap between batteries and capacitors, may well enhance every aspect of electrical energy usage, from transportation to communications and computing. Here, we are using novel nanocarbons and electro-conducting polymer composites to design and fabricate high-power, high-energy supercapacitors. Click the title of any of these studies below to read further.
Directed Self-assembly of layered bucky aerogel (in prep)
Electrochemical properties of catalyst impregnated bucky paper (in prep)
The Method of Harmonic Detection of Resonance : Methods for studying mechanical resonances in micro- and nano-sized cantilevers are critical for developing micro- and nano-electromechanical based systems. We are using our patented novel technique, known as the “Harmonic Detection of Resonance”, which is entirely electrical in nature to measure resonances in commercially available silicon microcantilevers and cantilevered nanostructures (e.g. the multiwalled carbon nanotubes, coiled carbon nanotubes and ZnO nanowhiskers). The elegant efficiency of our HDR method lies in its ability to overcome parasitic capacitance that has significantly limited the capability of previous techniques. In addition to sensing the presence or absence of gases in the vicinity of a resonating micro-cantilever, we are using our HDR method to pioneer our understanding of the fundamental mechanism for electrically actuated mechanical resonances in semi-conducting nanowhiskers.