Genome-nanosurface interaction of titania nanotube arrays: evaluation of telomere, telomerase and NF-κB activities on an epithelial cell model

Schematic illustrations described the activation of pro-survival and cellular senescence activities via NF-κb inhibition upon the interaction from cells grown on TNA nanosurfaces.

Supercapacitor electrodes based on modified titania nanotube arrays on flexible substrates

Highly ordered titania nanotube arrays were synthesised on titanium metal foil through electrochemical anodisation. The annealed samples were characterised through scanning electron microscopy and X-ray diffraction analysis. The electrochemical characterisations of the arrays were done through cyclic voltammetry, galvanostatic charge discharge and electrochemical impedance spectroscopy analyses. The titania nanotube arrays exhibited a specific capacitance of 6.8 mF cm–2 at 5 mV s–1 scan rate, which is very much higher than that reported earlier. Pseudocapacitive metal oxides were deposited on these arrays forming composite supercapacitor electrodes and their supercapacitor properties were compared with same deposited on bare titanium foil substrates. Pseudocapacitive metal oxides deposited on these titania nanotube array substrates exhibited improved supercapacitor performance and stability over the same deposited on titanium foil substrates.

Carbon and Neon Ion Bombardment Induced Smoothing and Surface Relaxation of Titania Nanotubes

Titania nanotube arrays with their enormous surface area are the subject of much attention in diverse fields of research. In the present work, we show that not only 60 keV and 150 keV ion bombardment of amorphous titania nanotube arrays yields defect creation within the tube walls, but it also changes the surface morphology: the surface relaxes and smoothens in accordance with a curvature-driven surface material’s transport mechanism, which is mediated by radiation-induced viscous flow or radiation-enhanced surface diffusion, while the nanotubes act as additional sinks for the particle surface currents. These effects occur independently of the ion species: both carbon and neon ion bombardments result in comparable surface relaxation responses initiated by an ion energy of 60 keV at a fluence of 1 × 1016 ions/cm2. Using atomic force microscopy and contact angle measurements, we thoroughly study the relaxation effects on the surface topography and surface free energy, respectively. Moreover, surface relaxation is accompanied by further amorphization in surface-near regions and a reduction in the mass density, as demonstrated by Raman spectroscopy and X-ray reflectivity. Since ion bombardment can be performed on global and local scales, it constitutes a versatile tool to achieve well-defined and tunable topographies and distinct surface characteristics. Hence, different types of nanotube arrays can be modified for various applications.