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Title: Thin Solid Films


Full Journal Title: Thin Solid Films

ISO Abbreviated Title: Thin Solid Films

JCR Abbreviated Title: Thin Solid Films

ISSN: 0040-6090

Issues/Year: 24

Journal Country/Territory: Netherlands

Language: Multi-Language

Publisher: Elsevier Science SA

Publisher Address: PO Box 564, 1001 Lausanne, Switzerland

Subject Categories:

Materials Science Physics, Applied Physics, Condensed Matter: Impact Factor

Jaroniec, M. (1979), Effects of lateral interactions and surface heterogeneity in kinetics of adsorption from multicomponent gas-mixtures. Thin Solid Films, 59 (2), 249-254.

Full Text: T\Thi Sol Fil59, 249.pdf

Abstract: The kinetics of monolayer adsorption from multicomponent gas mixtures with lateral interactions in the adsorbed phase are discussed. Using the Bragg-Williams approximation the equations for sorption rate and kinetic adsorption isotherms are derived for homogeneous and heterogeneous solid surfaces with patchwise and random distribution of adsorption sites. The equilibrium adsorption isotherms generated by equations of sorption rate are also presented.

Jaroniec, M. and Garbacz, J.K. (1979), Unified description of the kinetics of localized and mobile monolayer adsorption from the gaseous-phase onto solid-surfaces. Thin Solid Films, 62 (2), 237-246.

Full Text: T\Thi Sol Fil62, 237.pdf

Abstract: A unified description of the kinetics of mobile and localized adsorption on solids is proposed. Theoretical considerations are presented for monolayer adsorption of single gases and binary gas mixtures with and without lateral interactions on homogeneous and heterogeneous solid surfaces. The equations for the sorption rate, derived in terms of this description, at equilibrium yield the majority of known adsorption isotherms and predict some new isotherms.

Jaroniec, M. (1980), Description of kinetics and equilibrium state of adsorption from multicomponent gas-mixtures on solid-surfaces. Thin Solid Films, 71 (2), 273-304.

Full Text: T\Thi Sol Fil71, 273.pdf

Garbacz, J.K. and Jaroniec, M. (1983), Theoretical description of adsorbate adsorbate association in the case of mobile monolayer adsorption of gases on homogeneous solid-surfaces. Thin Solid Films, 100 (1), 43-51.

Full Text: T\Thi Sol Fil100, 43.pdf

Notes: KKinitics

Abstract: The concept of adsorbate-adsorbate association is used for describing the mobile monolayer adsorption of gases on energetically homogeneous solid surfaces. Starting from the canonical partition functions for the mobile associated monolayers, a general procedure is proposed for deriving the analytical equations of adsorption isotherms. These equations are derived by applying different expressions for the free adsorbent surface area and by assuming the formation of double and multimolecular associates in the surface phase.

Jaroniec, M. (1983), Physical adsorption on heterogeneous solids: Present and future. Thin Solid Films, 100 (4), 325-328.

Full Text: T\Thi Sol Fil100, 325.pdf

Abstract: Physical adsorption of gases and of gas and liquid mixtures on heterogeneous solids is briefly reviewed. A special emphasis is given to the outlook for the future theoretical work in this field. The elaboration of a unified description of physical adsorption on heterogeneous solids at fluid-solid interfaces and a standard method for evaluating the energy distribution function seem to be the most important problems in physical adsorption.

Dabrowski, A., Jaroniec, M. and Garbacz, J.K. (1983), Theory of multilayer adsorption from multicomponent liquid-mixtures on homogeneous solid-surfaces. Thin Solid Films, 103 (4), 399-415.

Full Text: T\Thi Sol Fil103, 399.pdf

Abstract: Multilayer adsorption from multicomponent liquid mixtures on energetically homogeneous solid surfaces is discussed in terms of statistical thermodynamics. The canonical partition function is formulated for a multilayer surface phase consisting of molecules of identical molecular sizes. General relationships defining the equilibrium state are considered and are used to derive analytical equations for the adsorption isotherms.

Jaroniec, M., Piotrowska, J. and Bülow, M. (1983), Adsorption of mixtures of methane and krypton on CAA zeolite. II. Analysis of the experimental-data using Freundlich-type and Dubinin-Radushkevich-type equations derived by assuming similar heterogeneity parameters for single-gas adsorption. Thin Solid Films, 106 (3), 219-224.

Full Text: T\Thi Sol Fil106, 219.pdf

Abstract: Equations for mixed-gas adsorption isotherms were derived on the basis of the integral equation of the adsorption isotherm by assuming constant differences in the adsorption energies for all types of adsorption sites. The application of Freundlich- and Dubinin-Radushkevich-type isotherms to the interpretation of experimental data for methane-krypton mixtures is also presented.

Notes: highly cited

? Decher, G., Hong, J.D. and Schmitt, J. (1992), Buildup of ultrathin multilayer films by a self-assembly process. III. Consecutively alternating adsorption of anionic and cationic polyelectrolytes on charged surfaces. Thin Solid Films, 210 (1-2), 831-835.

Full Text: 1992\Thi Sol Fil210, 831.pdf

Abstract: A solid substrate with a positively charged planar surface is immersed in a solution containing an anionic polyelectrolyte and a monolayer of the polyanion is adsorbed. Since the adsorption is carried out at relatively high concentrations of polyelectrolyte, a large number of ionic residues remain exposed to the interface with the solution and thus the surface charge is effectively reversed. After rinsing in pure water the substrate is immersed in the solution containing a cationic polyelectrolyte. Again a monolayer is adsorbed but now the original surface charge is restored. By repeating both steps in a cyclic fashion, alternating multilayer assemblies of both polymers are obtained. The buildup of the multilayer films was followed by UV/vis spectroscopy and small angle X-ray scattering (SAXS). It is demonstrated that multilayer films composed of at least 100 consecutively alternating layers can be assembled.

Keywords: Monolayers

Creighton, J.R. (1994), The surface chemistry and kinetics of tungsten chemical vapor deposition and selectivity loss. Thin Solid Films, 241 (1-2), 310-317.

Full Text: T\Thi Sol Fil241, 310.pdf

Abstract: The mechanism of tungsten chemical vapor deposition (CVD) using hydrogen reduction of tungsten hexafluoride is reviewed, with emphasis on the relevant fundamental surface chemistry and kinetics. We also briefly review the kinetics and mechanism of selectivity loss involving tungsten subfluorides. Most kinetic studies of the H2 + WF6 reaction for typical low pressure CVD conditions report a phenomenological rate law for deposition that is zeroth order in WF6 pressure and 1/2-order in H2 pressure. Unfortunately, most of the reaction mechanisms reported to yield the observed rate law are inconsistent with the known (or estimated) surface chemical properties of H2 and WF6 on tungsten. There are also many conditions where the accepted rate law is not valid. For instance, as the H2 pressure is lowered and becomes comparable with the WF6 pressure, the deposition rate drops to zero. Under these conditions hydrogen chemisorption is apparently completely quenched and the surface is saturated with adsorbed fluorine. Just above the H2 pressure threshold the deposition rate is first order rather than 1/2-order with respect to H2. In this regime the WF6 pressure dependence is also strongly negative order rather than zeroth order. All the deviations from the normal rate law can be qualitatively explained using a Langmuir-Hinshelwood reaction mechanism with competitive adsorption. An important intrinsic mechanism of selectivity loss that occurs during tungsten CVD involves tungsten transport by the formation and disproportionation of volatile tungsten subfluorides. We present some recent measurements of the tungsten subfluoride formation rate using the microbalance technique.

Angelova, A., Vollhardt, D. and Ionov, R. (1996), Domain pattern instability of a lipid monolayer induced by adsorption/desorption of a cyanine dye. Thin Solid Films, 285, 85-89.

Full Text: T\Thi Sol Fil285, 85.pdf

Abstract: Brewster angle microscopy (BAM) is applied for studying the in-plane morphology of a cationic lipid monolayer and its interaction with a novel, water-soluble, J-aggregate forming, negatively charged carbocyanine dye. A methodology of monolayer compression/recompression is followed to influence the dye crystallization upon adsorption from an aqueous subsolution at a charged interface. Crystalline domains of a dendritic type are observed in the lipid monolayer compressed on a pure water subphase. Dye aggregation and crystalline nucleation is established by means of BAM for 2D lipid densities corresponding to the onset of the main phase transition of the composite monolayer. Subphase conditions, which prevent the nucleation of lipid 2D crystalline phase domains, are found to not favor dye crystallization at the interface. Dye adsorption and aggregation is established to be partially irreversible upon monolayer decompression. Dye desorption is related to the observation of stripe-like objects in the lipid monolayer, developing undulation instability, which produces non-equilibrium 2D labyrinthine patterns with time.

Kusano, H., Kimura, S., Kitagawa, M. and Kobayashi, H. (1997), Application of cellulose Langmuir-Blodgett films as humidity sensors, and characteristics of the sorption of water molecules into polymer monolayers. Thin Solid Films, 295 (1-2), 53-59.

Full Text: T\Thi Sol Fil295, 53.pdf

Abstract: Palmitoil cellulose Langmuir-Blodgett (LB) films have been prepared on quartz crystal oscillators in the fabrication of novel humidity sensors. The water sorption characteristics of the cellulose LB humidity sensors were investigated quantitatively by the microbalance method using a quartz oscillator. The dependence of the frequency difference of the oscillator with the adsorption of water molecules on the number of monolayers in the film and the temporal change have been measured under a wide range of fixed relative humidity conditions. The humidity dependence of the sorption characteristics falls into two regions: the lower relative humidity region shows slow desorption/sorption and a linear dependence on the number of monolayers in the film, and the higher relative humidity region shows a rapid desorption/sorption process and is independent of the number of monolayers.

In the lower relative humidity region, water sorption proceeds through the well ordered palmitoil cellulose LB monolayers onto various sites with different sorption energies in the glucose base unit. In the higher relative humidity region near saturation, the sorption is controlled simply by the free condensation of water molecules onto the him surface. These characteristics can be expressed numerically by the so-called Freundlich isotherm and the Polanyi theory. The applications of LB monolayer-based humidity sensors are briefly discussed. (C) 1997 Elsevier Science S.A.

Keywords: Langmuir-Blodgett Films (Lb Films), Monolayers, Polymers, Sensors, FT-IR

Matsumaru, K., Fukuyama, H., Susa, M. and Nagata, K. (1998), Evaporation from synthetic incinerator ashes melted by plasma arc. Thin Solid Films, 316 (1-2), 105-110.

Full Text: T\Thi Sol Fil316, 105.pdf

Abstract: Synthetic incinerator ashes of 40 mass %SiO2–40CaO–20Al2O3 (named Glass) and 36 mass %SiO2–36CaO–18Al2O3–10Fe2O3 (named Fe-Glass) were melted by argon plasma arc, with iron rods used for arc ignition. A direct current transferred type plasma generator was used with an output power of 6 kW. During arc melting, the iron rod was melted and located in the centre of the molten ash. The temperature at the boundary between the iron and ash melts was 2200 K and that at the edge of the ash 1870 K. X-Ray diffraction showed that the deposit vaporised from Glass was composed of Fe, FeSi and amorphous SiO2. The evaporation rates from Glass and Fe-Glass were 3.8×10−4 g/s and 1.4×10−4 g/s, respectively. It has been concluded that the rate of evaporation from the molten ash is affected by the vaporisation reaction which determines the oxygen partial pressure in the whole system.

Keywords: Synthetic Incinerator Ashes, Argon plasma Arc, Evaporation

Raposo, M., Mattoso, L.H.C. and Oliveira, O.N. (1998), Adsorption isotherms of poly(o-methoxyaniline). Thin Solid Films, 327-329, 739-742.

Full Text: T\Thi Sol Fil327, 739.pdf

Abstract: Adsorption isotherms have been obtained for poly(o-methoxyaniline) (POMA) deposited from aqueous solutions onto glass substrates using UV-visible spectroscopy. Since the peaks in the UV-vis spectra are shifted due to dedoping of POMA during the adsorption process, isosbestic points had to be determined for estimating the amount of polymer adsorbed per unit area. Experiments were carried out at various temperatures. For 25°C, the data could be fitted with a Gu isotherm equation, which indicates that the formation of aggregates occurs for high concentrations. For concentrations below 0.25 g/l, the data could be fitted with a traditional Langmuir-type adsorption isotherm. A Langmuir isotherm also applies to data at the other temperatures employed, viz. 15°C, 40°C, 60°C and 80°C, far which the corresponding equilibrium adsorption constants were calculated. The enthalpy, entropy and free energy adsorption values were then estimated, which showed that POMA adsorption is mostly entropy controlled. (C) 1998 Published by Elsevier Science S.A. All rights reserved.

Keywords: Self-Assembly, Adsorption, Poly(o-methoxyaniline), Polyvinylsulfonic Acid, Adsorption Enthalpy, Isosbestic Point, Conjugated Polyions, Films, Surfactants, Surfaces

Nguyen, Q.T., Kidder, J.N. and Ehrman, S.H. (2002), Hybrid gas-to-particle conversion and chemical vapor deposition for the production of porous alumina films. Thin Solid Films, 410 (1-2), 42-52.

Full Text: T\Thi Sol Fil410, 42.pdf

Abstract: Porous alumina films can be found in a wide variety of materials, including filters, thermal insulation components, dielectrics, biomedical and catalyst supports, coatings and adsorbents. Production methods for these films are as equally diverse as their applications. In this work, a hybrid process based upon chemical vapor deposition and gas-to-particle conversion is presented as an alternative technique for producing porous alumina films, with the main advantages of solvent-free, low substrate-temperature operation. In this process, nanoparticles were produced in the vapor phase by reaction of aluminum acetylacetonate in the presence of oxygen. Downstream of this reaction zone, these nanoparticles were collected via thermophoresis onto a cooled substrate, forming a porous film. Some deposited films were subjected to post-processing in the form of annealing in air. Fourier-transform infrared spectra and X-ray energy-dispersive spectroscopy analysis confirmed the production of alumina at processing temperatures above 973 K. X-Ray diffraction revealed that the films were amorphous. Film thickness, ranging from 30 to 250 m, and the average deposition rate were determined from scanning electron microscopy results. From transmission electron microscopy, the average primary particle size was determined to be approximately 18 nm and the formation of nanoparticle aggregates was evident. Annealing of the films at temperatures ranging from 523 to 1173 K in the presence of air did not have an effect on particle size. The specific surface area of the powder composing the films ranged from 10 to 185 m2 g-1, as determined from nitrogen gas adsorption by the Brunauer-Emmett-Teller method. (C) 2002 Elsevier Science B.V All rights reserved.

Keywords: Aluminum Oxide, Chemical Vapor Deposition (CVD), Deposition Process, Fourier-Transform Infrared Spectroscopy (Ftir), High-Pressure Compaction, Surface-Area, Water-Vapor, Acetylacetonate, Phase, Kinetics, Growth, Size




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