Porous Silicon (PS) layers have been prepared from p-type silicon wafers of (100) orientation. SEM, XRD, FTIR and PL studies were done to characterize the surface morphological and optical properties of PS. The porosity of the PS samples was determined using the parameters obtained from SEM images by geometric method. The refractive index values of the PS samples as a function of poros...

Electron emission induced by X-ray radiation in secondary-emission porous materials was investigated. © 2000 MAIK “Nauka/Interperiodica”. Secondary-emission porous materials are widely used as a working substance in electromagnetic and corpuscular radiation detectors [1–5]. The detection process in this case is governed by the interaction between primary radiation and a porous material, fastpri...

Here we report the derivatization of mesoporous TiO2 thin films for the preparation of H2O2 amperometric sensors. The coordination of the bifunctional ligand 1,10 phenantroline, 5,6 dione on the surface Ti(IV) ions provides open coordination sites for Fe(II) cations which are the starting point for the growth of a layer of Prussian blue polymer. The porous structure of the mesoporous TiO2 allow...

Metal-organic and covalent organic frameworks are porous materials characterized by outstanding thermal stability, high porosities and modular synthesis. Their repeating structures offer a great degree of control over pore sizes, dimensions and surface properties. Similarly precise engineering at the nanoscale is difficult to achieve with discrete molecules, since they rarely crystallize as por...

Porous GaSb has been formed by Ga ion implantation into crystalline GaSb substrates at either room temperature or 180 C. The morphology has been characterized using scanning electron microscopy and the atomic structure was determined using extended x-ray absorption fine structure spectroscopy. Room-temperature implantation at low fluences leads to the formation of 20-nm voids though the materia...

Open-framework germanates are a group of germanium oxides with a well-defined porous structure, suitable for ion-exchange and gas adsorption applications. Recently, Ni incorporation into the porous structure by establishing Ge-O-Ni bonds with the molecular complexes [Ni(H2N(CH2)2NH2)2] was realized. We investigate the optical and electronic features of these systems (SUT-1 and SUT-2) from first...

Porous solids have an important role in addressing some of the major energy-related problems facing society. Here we describe a porous solid, α-MnO2, with a hierarchical tetramodal pore size distribution spanning the micro-, meso- and macro pore range, centred at 0.48, 4.0, 18 and 70  nm. The hierarchical tetramodal structure is generated by the presence of potassium ions in the precursor solut...

We report a simple and convenient method for fabricating ordered porous structure in a polymeric thin film. A temporarily stabilized water-in-oil emulsion, where aqueous droplets were dispersed in the medium of polymer-organic solvent solution, was utilized for the preparation of porous structure. The water-in-oil emulsion was simply prepared by sonicating the mixture of water and polymer-organ...

The acoustic properties of a porous sheet of medium static air flow resistivity (around 10,000 N m s(-4)), in which a periodic set of circular inclusions is embedded and which is backed by a rigid plate, are investigated. The inclusions and porous skeleton are assumed motionless. Such a structure behaves like a multi-component diffraction grating. Numerical results show that this structure pres...

This paper describes a novel hybrid method for fluid simulation of saturating anisotropic porous material via fluid-structure coupling. Our framework employs particle finite element method (PFEM) that not only adopts Lagrangian scheme to model the motion of freely-moving particles, but also produces the extended Delaunay Tessellation to furnish the governing equations with FEM discretization. W...