To overcome the problems of gene and drug delivery, nanotechnology has gained interest in recent years. Nanosystems with different compositions and biological properties have been extensively investigated for drug and gene delivery applications. Nanotechnology in drug delivery has been manifested into nanoparticles that can have unique properties both in vitro and in vivo, especially in targete...

Photoluminescence properties of semiconducting single-wall carbon-nanotube (s-SWNT) thin films with different metallic single-wall carbon-nanotube (m-SWNT) concentrations are reported. s-SWNT purified samples are obtained by polymer-assisted selective extraction. We show that the presence of a few m-SWNTs in the sample generates a drastic quenching of the emission. Therefore, the highly purifie...

Freestanding Si-Ti-Ni alloy particles/reduced graphene oxide/single wall carbon nanotube composites have been prepared as an anode for lithium ion batteries via a simple filtration method. This composite electrode showed a 9% increase in reversible capacity, a two-fold higher cycle retention at 50 cycles and a two-fold higher rate capability at 2 C compared to pristine Si-Ti-Ni (STN) alloy elec...

Herein, the interaction of hydrogen sulfide with inside and outside single-wall carbon nanotube of (5,0) and (5,5) is investigated using density functional theory at B3LYP/6-31G* level of theory in the gaseous phase by Gaussian 09. The adsorption energies, thermodynamic properties, highest occupied molecular orbital, lowest unoccupied molecular orbital, energy gaps, and partial charges of the i...

We present photoluminescence studies of individual semiconducting single-wall carbon nanotubes at room and cryogenic temperatures. From the analysis of spatial and spectral features of nanotube photoluminescence, we identify characteristic signatures of unintentional exciton localization. Moreover, we quantify the energy scale of exciton localization potentials as ranging from a few to a few te...

Even though isolated defect-free single-wall carbon nanotubes are straight, bundles of chiral single-wall carbon nanotubes are often helical according to our observations using high-resolution electron microscopy. The driving force for the formation of such helices is the energy gain associated with the optimum orientational alignment of neighboring nanotubes. Our total energy calculations allo...

Single walled carbon nanotubes represent the future of structural aerospace vehicle systems due to their unparalleled strength characteristics and demonstrated multifunctionality. This multifunctionality rises from the CNT’s unique capabilities for both metallic and semiconducting electron transport, electron spin polarizability, and band gap modulation under strain. By incorporating the use of...

Focused ion beam (FIB) techniques have found many applications in nanoscience and nanotechnology applications in recent years. However, not much work has been done using FIB to fabricate carbon nanotube devices. This is mainly due to the fact that carbon nanotubes are very fragile and energetic ion beam from FIB can easily damage the carbon nanotubes. Here we report the fabrication of carbon na...

Metallic single wall carbon nanotube devices were characterized using low temperature transport measurements to study how the growth conditions affect defect formation in carbon nanotubes. Suspended carbon nanotube devices were grown in situ by a molecular beam growth method on a pair of catalyst islands located on opposing Au electrodes fabricated by electron beam lithography. The authors pres...