Some electronic properties and morphological features of hybrid material DNA–SWCNT thin films

Thin films of hybrid material (ssDNA–SWCNT) prepared by ultrasonic mixing of both materials in water have been examined from the viewpoint of electrical, magnetic and optical properties, and morphological features to probe the possibly induced novel functions due to mutual interactions. Enclosing of DNA molecules inside a SWCNT is confirmed by the image and its motion. The temperature dependence of electrical resistivities is best-fitted to the two-dimensional variable-range-hopping regime. The radial breathing mode of the Raman spectra of the SWCNT exhibits significant modification due to interaction with DNA. The expected change in magnetic susceptibilities is not found in this case.     

Consequences of nanoparticle diameter and solid–liquid interfacial layer on the SWCNT/EO nanofluid flow over various shaped thin slendering needles

In this research article, we have discussed about the boundary layer flow of single walled CNT– engine oil nanofluid over three distinct nonlinearly slendering isothermal thin needles of cone, paraboloid and cylinder shapes with zero mass flux at boundary condition. We have considered the effects of diameter of SWCNT and solid–liquid interfacial layer in the thermal conductivity model of the nanofluid. We also combined single phase and double phase model to construct our model. Then after some transformations the governing equations are solved numerically and staged the effects of diameter of SWCNT and nanolayer on the characteristics of the flow through proper graphs and charts. Here, we observed that the presence of the SWCNT decreases both temperature and heat flow in the system. Also we established that cone shaped needle is the most affected by the material parameters of consideration.     

Theoretical studies on the geometrical and electronic structures of supramolecule bis(2,2′-bipyridine)-5-amino-1,10-phenanthroline ruthenium(II)/functionalized SWCNT dyads

Functionalization of carbon nanotube (CNT) with multiple redox and photo active entities is one of the extensive processes due to its importance in building molecular or supramolecular electronic devices, solar energy storage and conversion systems. Thus, to have better understanding about structural aspects and correct electronic structure of these large systems, the quantum studies have gained increased popularity. In present study, we have investigated the structural and electronic properties of functionalized CNTs (fCNTs) with [Ru(bpy)₂(5-NH₂-1,10-phen)]⁺², (Ru-bpy-phen)⁺², supramolecule based on DFT calculations. Main attention has been applied to obtain stable configuration, binding energies and effect of functionalization on electronic behavior of the selected supramolcule. We also evaluate the effect of nanotube’s diameter and chirality on electronic properties of considered supramolecule. Calculated binding energies show that interaction between the (Ru-bpy-phen)⁺² and the host CNTs depends on the tube diameter while the chirality doesn’t affect significantly on the binding nature of respected complex. We have also investigated the influence of non-local dispersion interactions (vdW) and temperature on the stability and electronic structure of the considered system. Results obtained from the ab initio MD simulations showed that increasing the temperature can affect the distance between C and N atoms in the linkage position. The charge analysis indicates the existence of remarkable charge transfer between (Ru-bpy-phen)⁺² as donor and fCNTs as acceptor moieties in the isolated molecule. In the presence of vdW forces and at higher temperature, the charge transfer was decreased but the direction of transferred charge remains unchanged.