The preparation of stoichiometric mercury cadmium telluride surfaces

1987 ◽  
Vol 65 (8) ◽  
pp. 1044-1046
Author(s):  
R. B. North ◽  
W. M. Lau
Keyword(s):  
Surface Treatment ◽  
Cadmium Telluride ◽  
Photoelectron Spectroscopy ◽  
Chemical Etching ◽  
Mercury Cadmium Telluride ◽  
Surface Composition ◽  
Surface Enrichment ◽  
Air Oxidation ◽  
X Ray

A technique involving cathodization of an anodized surface has been proposed as a surface treatment of mercury cadmium telluride substrates in the fabrication of infrared-sensitive devices. The resultant surface was analyzed with X-ray photoelectron spectroscopy and compared with surfaces produced by cleavage, sputtering, and chemical etching. It was found that the cathodized surface had a surface composition close to the bulk stoichiometry. The first monolayer of the surface was enriched in mercury and depleted in cadmium. This surface was also more inert towards air oxidation than the Br–methanol treated surface, probably because of the surface enrichment of mercury.

scholarly journals Easy and Fast Fabrication of Self-Cleaning and Anti-Icing Perfluoroalkyl Silane Film on Aluminium

Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 234 ◽  
Author(s):  
Peter Rodič ◽  
Barbara Kapun ◽  
Matjaž Panjan ◽  
Ingrid Milošev
Keyword(s):  
Surface Topography ◽  
Photoelectron Spectroscopy ◽  
Chemical Etching ◽  
Surface Composition ◽  
Infrared Camera ◽  
Ethanol Solution ◽  
X Ray ◽  
Chemical Surface ◽  
Fecl3 Solution ◽  
Self Cleaning

A combination of the chemical etching process in FeCl3 solution and chemical surface grafting by immersion in ethanol solution containing 1H,1H,2H,2H-perfluorodecyltriethoxysilane is a viable route to achieve a hierarchical surface topography and chemical bonding of silane molecules on an aluminium surface leading to (super)hydrophobic characteristics. Characterisation of untreated and treated aluminium surfaces was carried out using contact profilometry, optical tensiometry, scanning electron microscopy coupled with energy-dispersive spectroscopy and X-ray photoelectron spectroscopy to define the surface topography, wettability, morphology and surface composition. Additionally, the dynamic characteristics were evaluated to define bouncing and the self-cleaning effect. A thermal infrared camera was employed to evaluate anti-icing properties. The micro/nano-structured etched aluminium surface grafted with perfluoroalkyl silane film showed excellent superhydrophobicity and bounce dynamics in water droplet tests. The superhydrophobic aluminium surface exhibited the efficient self-cleaning ability of solid pollutants as well as improved anti-icing performance with melting delay.

Effect of Surface Treatment on the Mechanical Performance of PPTA-Pulp Reinforced Rubber Composites in Supercritical Carbon Dioxide Fluid

2017 ◽  
Vol 898 ◽  
pp. 2231-2238
Author(s):  
Ming Lin Qin ◽  
Jing Liu ◽  
Ke Qing Han ◽  
Fan Yu ◽  
Cui Qing Teng ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Surface Treatment ◽  
Photoelectron Spectroscopy ◽  
Mechanical Performance ◽  
Surface Composition ◽  
Rubber Matrix ◽  
X Ray Diffraction ◽  
X Ray ◽  
Supercritical Carbon

A facile surface modification method for PPTA-pulp was developed to improve the adhesion to rubber matrix. Tensile strength tests and SEM were used to evaluate the adhesion of PPTA-pulp with rubber matrix, and the results indicated that surface treatment of PPTA pulp in supercritical carbon dioxide fluid was an efficient method to increase interfacial adhesion between PPTA-pulp and rubber matrix. Attenuated Toyal reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to investigate the surface structure and composition of untreated and treated PPTA-pulp in supercritical carbon dioxide fluid. The results indicated that the interaction of macromolecules, the crystal structure and the surface composition of PPTA-pulp changed during supercritical carbon dioxide fluid, particularly for the surface morphology and composition.

CO2 Reduction to Propanol by Copper Foams: A Pre- and Post-Catalysis Study

2020 ◽  
Author(s):  
Jennifer A. Rudd ◽  
Ewa Kazimierska ◽  
Louise B. Hamdy ◽  
Odin Bain ◽  
Sunyhik Ahn ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Photoelectron Spectroscopy ◽  
Carbon Capture ◽  
Surface Composition ◽  
Co2 Reduction ◽  
Structural Rearrangement ◽  
Copper Electrode ◽  
Ex Situ ◽  
X Ray ◽  
Copper Electrodes

The utilization of carbon dioxide is a major incentive for the growing field of carbon capture. Carbon dioxide could be an abundant building block to generate higher value products. Herein, we describe the use of porous copper electrodes to catalyze the reduction of carbon dioxide into higher value products such as ethylene, ethanol and, notably, propanol. For <i>n</i>-propanol production, faradaic efficiencies reach 4.93% at -0.83 V <i>vs</i> RHE, with a geometric partial current density of -1.85 mA/cm<sup>2</sup>. We have documented the performance of the catalyst in both pristine and urea-modified foams pre- and post-electrolysis. Before electrolysis, the copper electrode consisted of a mixture of cuboctahedra and dendrites. After 35-minute electrolysis, the cuboctahedra and dendrites have undergone structural rearrangement. Changes in the interaction of urea with the catalyst surface have also been observed. These transformations were characterized <i>ex-situ</i> using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. We found that alterations in the morphology, crystallinity, and surface composition of the catalyst led to the deactivation of the copper foams.

scholarly journals Dual Light- and pH-Responsive Composite of Polyazo-Derivative Grafted Cellulose Nanocrystals

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1725 ◽  
Author(s):  
Xiaohong Liu ◽  
Ming Li ◽  
Xuemei Zheng ◽  
Elias Retulainen ◽  
Shiyu Fu
Keyword(s):  
Cellulose Nanocrystals ◽  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
X Ray Diffraction ◽  
Responsive Materials ◽  
X Ray ◽  
Ph Response ◽  
Transmission Electron ◽  
Ft Ir ◽  
Hexyl Methacrylate

As a type of functional group, azo-derivatives are commonly used to synthesize responsive materials. Cellulose nanocrystals (CNCs), prepared by acid hydrolysis of cotton, were dewatered and reacted with 2-bromoisobuturyl bromide to form a macro-initiator, which grafted 6-[4-(4-methoxyphenyl-azo) phenoxy] hexyl methacrylate (MMAZO) via atom transfer radical polymerization. The successful grafting was supported by Fourier transform infrared spectroscopy (FT-IR) and Solid magnetic resonance carbon spectrum (MAS 13C-NMR). The morphology and surface composition of the poly{6-[4-(4-methoxyphenylazo) phenoxy] hexyl methacrylate} (PMMAZO)-grafted CNCs were confirmed with Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The grafting rate on the macro-initiator of CNCs was over 870%, and the polydispersities of branched polymers were narrow. The crystal structure of CNCs did not change after grafting, as determined by X-ray diffraction (XRD). The polymer PMMAZO improved the thermal stability of cellulose nanocrystals, as shown by thermogravimetry analysis (TGA). Then the PMMAZO-grafted CNCs were mixed with polyurethane and casted to form a composite film. The film showed a significant light and pH response, which may be suitable for visual acid-alkali measurement and reversible optical storage.

Surface Composition of Free Mixed NaCl/Na2SO4 Nanoscale Aerosols Probed by X-ray Photoelectron Spectroscopy

2018 ◽  
Vol 122 (10) ◽  
pp. 2695-2702 ◽  
Author(s):  
E. Antonsson ◽  
C. Raschpichler ◽  
B. Langer ◽  
D. Marchenko ◽  
E. Rühl
Keyword(s):  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
X Ray

Surface composition and electronic structure of Ni2+xMn1−xGa studied by X-ray photoelectron spectroscopy

2006 ◽  
Vol 600 (18) ◽  
pp. 3749-3752 ◽  
Author(s):  
C. Biswas ◽  
S. Banik ◽  
A.K. Shukla ◽  
R.S. Dhaka ◽  
V. Ganesan ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
X Ray

scholarly journals Succinic acid in aqueous solution: connecting microscopic surface composition and macroscopic surface tension

2014 ◽  
Vol 16 (39) ◽  
pp. 21486-21495 ◽  
Author(s):  
Josephina Werner ◽  
Jan Julin ◽  
Maryam Dalirian ◽  
Nønne L. Prisle ◽  
Gunnar Öhrwall ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Surface Tension ◽  
Succinic Acid ◽  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
Md Simulations ◽  
Vapor Interface ◽  
X Ray ◽  
Ph Values ◽  
Microscopic Surface

The water–vapor interface of aqueous solutions of succinic acid, where pH values and bulk concentrations were varied, has been studied using surface sensitive X-ray photoelectron spectroscopy (XPS) and molecular dynamics (MD) simulations.

Effect of Microstructural Characteristics of Electroless Nickel Metallisation on Solderability to Pb-Free Solder Alloys

2005 ◽  
Author(s):  
Changqing Liu ◽  
David A. Hutt ◽  
Dezhi Li ◽  
Paul P. Conway
Keyword(s):  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
Bulk Composition ◽  
Industrial Process ◽  
Surface Characteristics ◽  
Electroless Nickel ◽  
X Ray ◽  
N2 Atmosphere ◽  
Different Temperatures ◽  
Free Solder

This paper aims to gain an insight into the correlation between the microstructure and surface composition of electroless Ni-P and its behaviour during soldering with Pb free alloys including Sn-3.8Ag-0.7Cu, Sn-3.5Ag and Sn-0.7Cu. Ni-P coatings with different P contents were produced through an industrial process on copper metal substrates. The surface morphology of these coatings was observed by Scanning Electron Microscopy (SEM) and the bulk composition was analyzed by means of Energy Dispersive X-ray analysis (EDX). The mechanical properties of the coatings were evaluated by nano-indentation testing under different maximum loads. However, to understand the behaviour of P in Ni-P coatings and deterioration of the coating surfaces during exposure to air, the surfaces of the coatings were also characterised by X-ray Photoelectron Spectroscopy (XPS) for storage at different temperatures. The dependence of the solderability of Ni-P coatings on the storage time and temperature was investigated by wetting balance testing, using an inactive or active flux with or without an inert N2 atmosphere. Finally, the solderability of Ni-P coatings to Pb free solders is correlated with their composition and microstructure (e.g. surface characteristics).

Carbon Supported Pt+Os Catalysts for Methanol Oxidation

2002 ◽  
Vol 57 (2) ◽  
pp. 193-201 ◽  
Author(s):  
Gülsün Gökağaç ◽  
Brendan J. Kennedy
Keyword(s):  
Methanol Oxidation ◽  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
Carbon Support ◽  
Methanol Oxidation Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Metal Metal ◽  
Metal Support

11% Pt/C, 10% Pt + 1%Os/C, 9% Pt + 2%Os/C, 8% Pt + 3%Os/C, 7% Pt + 4%Os/C, 6% Pt + 5%Os/C and 5%Pt + 6% Os/C catalysts have been prepared for methanol oxidation reaction. Transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and cyclic voltammetry have been used to understand the nature of the species present in these catalysts. 7% Pt + 4% Os/C was the most active catalyst, while 8% Pt + 3% Os/C was the least active one. It is found that the metal particle size and distribution on the carbon support, the surface composition and the oxidation states of the metal particles, the metal-metal and metal support interactions are important parameters to define the activity of the catalyst.

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