Multicomponent Diamond-Like Semiconductors Based on the InBV–CdS System: Bulk and Surface Properties

Semiconductors - According to developed methods, in the fields of the mutual solubility of initial binary compounds (InP, InSb, and CdS), solid solutions of the InP–CdS and InSb–CdS...     

New Adsorbents Based on the InSb–CdSe Heterosystem. Volumetric and Surface Properties

Protection of Metals and Physical Chemistry of Surfaces - Based on the InSb–CdSe heterovalent substitution system, new adsorbents have been obtained being solid solutions with the structure...     

Synthesis and Optical Absorption of Solid Solutions between InSb and II–VI Compounds

InSb–ZnSe, InSb–CdSe, and InSb–ZnTe substitutional solid solutions were synthesized. Optical measurements were carried out on films deposited by thermal evaporation in vacuum. The formation of substitutional solid solutions was inferred from the composition dependences of the band gap (estimated from the absorption edge) and x-ray diffraction data.     

Gas adsorption at the components of the GaAs-CdS system

Adsorption properties of the GaAs-CdS-system solid solutions and binary compounds are studied with respect to CO and NH₃ by the piezoelectric quartz microweighing, programmed thermal desorption, and IR-spectroscopy. Based on the experimental dependences (α_p = f(T), αT = f(P), αT = f(t)), thermodynamic and kinetic characteristics of adsorption, analysis of the surface chemical composition, the adsorbents’ acid-base and other physicochemical characteristics. With due allowance for electron structure of the adsorbate’s molecules, the mechanism and specifity of adsorption processes are determined as functions of the operation conditions and system composition. By comparing the adsorption properties of the binary compounds (GaAs and CdS) with those of the solid solutions (GaAs) _x (CdS)_1−x , their similarities, as well as the specificity of the solid solutions as multicomponent systems, were revealed. Optimal adsorbent compositions to be used in primary transducers in the medicine-and environment-orientated sensors are found. Original Russian Text ? I.A. Kirovskaya, 2008, published in Zashchita Metallov, 2008, Vol. 44, No. 2, pp. 197–203.     

Preparation and Properties of ZnxCd1 – xSe Solid Solutions

ZnSe–CdSe substitutional solid solutions were prepared by isothermal diffusion over the entire composition range and characterized by x-ray diffraction and thermal analysis. The structure of the solid solutions was found to change from cubic to hexagonal between 30 and 40 mol % CdSe.     

Adsorptive and Electrical Properties of InSb–ZnSe Films

The band gap and electrical conductivity of InSb–ZnSe films are measured. Their composition dependences, as well as x-ray diffraction data, point to the formation of substitutional solid solutions. The effect of CO adsorption on the conductivity of InSb, ZnSe, and (InSb) _x (ZnSe)_{1 – x} solid solutions is studied. The results demonstrate that the temperature, pressure, and time dependences of conductivity, as well as those of adsorption, follow classical laws. The correlation between the adsorptive and electronic properties of the films confirms that adsorption centers and surface states have the same origin. The materials exhibiting high CO selectivity and sensitivity are used to produce solid-state gas sensors.     

Comparative Physical-Chemical Properties of Binary and Multicomponent Semiconductors in CdS–ZnSe and CdS–ZnS Systems

Solid substitution solutions in CdS–ZnSe and CdS–ZnS systems have been fabricated and certified. Bulk (crystal chemistry, structural, and optical) and surface (acid–base) properties of these solutions have been examined as compared to each other and their binary components. Regularities of changes in the investigated properties upon changes in the systems’ compositions and in a series of analogs have been established: these regularities have predominantly exhibited an extremal nature. Interrelations between the established regularities have been validated, which allows predicting, based only on bulk properties, the surface activity of advanced materials (fabricated solid solutions) toward gases of varied electronic nature—components of natural and technological media. Practical guidelines on application of these materials to produce appropriate sensors have been provided.