Physisorption on metal surfaces, and the tunneling currents through the adsorbed species, are calculated using a unified formalism that presents both problems on the same footing. Our method is based on a self-consistent LCAO approach whereby the different interaction parameters defining the bonds, and the tunneling currents, are calculated using the atomic properties of the atomic species form...

A bifunctional nanocatalyst composed of iron containing SBA-15 material modified with sulfonic acid groups was synthesized by a mechanochemical approach. A full characterization of the obtained nanocatalyst was performed by N2 physisorption isotherms analysis, transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and Fourier-Infrared Spectroscopy (FT-IR). The mechanochemically ...

Different physisorption properties by 2D and 3D isomers of Au_{n};{-} clusters are observed and used to probe the 2D to 3D structural transition. Strong Ar clustering occurs on planar Au_{n};{-} and the planar faces of the pyramidal Au20-. An abrupt change of Ar clustering at Au12- confirms the 2D to 3D structural transition at this size, where both isomers coexist. The minor 2D isomer can be t...

In this highlight we briefly review several of our recent theoretical studies focused on how the interplay between the chemical and the van der Waals interactions determines the bonding mechanism of several chemically functionalized π-conjugated organic molecules on non-magnetic and magnetic surfaces. In particular, we focus on the issue how to tailor the strength of the interaction between suc...

In this letter, pronounced hysteresis loops were observed in single-walled carbon nanotube-based field-effect transistors CNTFETs . The shift in threshold voltage was found to increase with increasing gate voltage sweep ranges. A significant enhancement in the charge storage stability over 14 days was obtained at room temperature after a two-stage hydrogen and air annealing process was applied ...

The physisorption of atomic hydrogen on graphene is investigated quantum mechanically using a semiempirical model for the lattice dynamics. A thermally averaged wave packet propagation describes the motion of the H atoms with respect to the membrane. Two graphene configurations, either supported on a silicone oxide substrate or suspended over a hole in the substrate, are considered. In both cas...

Hexagonally ordered mesoporous silica materials MCM-41 and SBA-15 have been synthesized and loaded with Ag nanoparticles, utilizing both chemical synthesis and ultrashort pulsed laser ablation in liquid. In laser ablation, a silver target, immersed in aqueous suspension of ordered mesoporous silica SBA-15, was irradiated by ultra-short laser pulses to generate silver nanoparticles. For comparis...

Multi-walled carbon nanotubes (CNTs) have been grown in situ on a SiO 2 substrate and used as gas sensors. For this purpose, the voltage response of the CNTs as a function of time has been used to detect H 2 and CO 2 at various concentrations by supplying a constant current to the system. The analysis of both adsorptions and desorptions curves has revealed two different exponential behaviours f...

This study explored the feasibility of using granular ferric hydroxide as adsorbent for the removal of NO3-N. Optimum conditions for NO3-N removal were found to be pH 5.0 and equilibrium time 80min. The equilibrium sorption isotherm was better described by Langmuir sorption isotherm model. The maximum sorption capacity of granular ferric hydroxide was 4.254mg/g at 298K. A comparison of four kin...