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Evolution of the morphology, composition, structural characteristics (lattice constant, microstrains, texturing), and optical and photoelectric properties of PbS films produced by chemical deposition in the presence of ammonium iodide and chromium (III) chloride at concentrations of up to 0.02 M is studied. According to the data of elemental analysis by energy-dispersive X-ray spectroscopy, the Cr content in PbS films nonmonotonically depends on the CrCl3 concentration, and the highest content is 1.08 at %. The size distribution of particles is monomodal, and the average size of particles forming the films varies from ~100 to ~225 nm at a nanoparticle content of 2–6%. The introduction of NH4I and CrCl3 into the reactor preserves the B1 cubic structure of PbS and yields an increase in the band gap Eg by 0.16–0.20 eV, a decrease in the dark resistance Rd, and an increase in the voltage sensitivity Us. The dependences of Eg and Us on the chromium-salt concentration in the reaction bath are of extreme character, with a maximum at 0.016 M of CrCl3, which is due to the nonmonotonic incorporation of chromium into the PbS lattice. The results of studies of the current–voltage characteristics of PbS(I) and PbS(I, Cr) thin-film layers are in good agreement with the data on the structural, optical, and photosensitivity properties. [ABSTRACT FROM AUTHOR]

Equilibrium processes in the "CuCl2–H2O–NaOH" system are studied with the consideration of the formation of low soluble phases of various compositions based on mathematical processing of experimental results from potentiometric titration using EQ-5 software. The values of instability constants of copper complex ions and dynamic equilibrium constants of copper low soluble compounds are calculated along with their stoichiometric compositions and regions of stable existence. [ABSTRACT FROM AUTHOR]

We have studied the morphology and thermal stability of thin Cu1.8Se films produced by hydrochemical deposition at 333 K using sodium selenosulfate. The crystal structure and phase composition of the films have been determined by X-ray diffraction and scanning electron microscopy. Heat treatment in the temperature range 453–563 K has been shown to change the phase composition and morphology of the copper(I) selenide films, as well as the size of their structural elements. [ABSTRACT FROM AUTHOR]

Abstract: Equilibrium processes that occur in the ZnCl2-H2O-NaOH system are studied via the potentiometric titration of zinc chloride in the 0.00006-1.01 mol/L range of concentrations. Based on mathematical simulations, a number of polynuclear structures and soluble phases are identified in the system. Values of the instability constants of complex forms and the constants of the dynamic equilibria of weakly soluble zinc compounds are calculated, along with their stoichiometric compositions and areas of sustainable existence. Refined boundary conditions are determined, along with areas of the formation of ZnSe and ZnS when they are precipitated using sodium selenosulfate and thiourea, respectively. ZnSe and ZnS layers around 1000 and 200 nm thick are obtained via hydrochemical deposition on glass-ceramic substrates. Based on electron microscopy data, it is concluded that the layers consist of spherical aggregates with mean sizes of around 350-450 nm for ZnSe and 50-200 nm for ZnS, generated from primary particles with sizes of around 20-60 and 20-30 nm, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The systematized results of studies of the composition, morphology, structure, optical properties, and conductivity of hydrochemically deposited copper(I) selenide thin films (Cu1.8Se) with the thickness of 390-400 nm are reported. The studies are carried out using scanning electron microscopy, energy-dispersive analysis, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The hole conductivity of the layers is established by the thermopower technique. The optical band gap determined from the results of studies of optical absorbance and diffuse reflection spectra of the films at 298 K is 2.5 and 1.84 eV for direct and indirect optical transitions, respectively. [ABSTRACT FROM AUTHOR]

The Cu2S and SnS2 layers have been prepared by the chemical bath deposition method. The results of SEM and EDX analyses confirm a high stoichiometry of the synthesized semiconductor thin films. The optical properties of the Cu2S and SnS2 layers have been studied, and the optical band gap values have been determined. [ABSTRACT FROM AUTHOR]

Chemical deposition from aqueous environments has significant perspective among existing methods of obtaining Cu2Se and ZnSe thin films. This method eliminates using complex expensive equipment, high-temperature heating, and deep vacuum. In this work, the calculation method for predicting the border conditions for the formation of individual metal chalcogenides phases was presented and widely tested on practice. Energy-dispersive analysis was used to investigate the elemental composition of the films. According to the results of thermoelectric power method, the layers had hole type conductivity. [ABSTRACT FROM AUTHOR]

The potentiometric titration of tin chloride SnCl2 is performed in the concentration range of 0.00009-1.1 mol/L with a solution of sodium hydroxide NaOH. According to potentiometric titration data based on modeling equilibria in the SnCl2-H2O-NaOH system, basic equations are generated for the main processes, and instability constants are calculated for the resulting hydroxo complexes and equilibrium constants of low-soluble tin(II) compounds. The data will be of interest for specialists in the field of theory of solutions. [ABSTRACT FROM AUTHOR]

Thin films of indium(III) sulfide have been prepared by chemical precipitation from aqueous solutions containing indium(III) nitrate, thioacetamide, tartaric acid, and hydroxylamine hydrochloride at 333-368 K. Kinetics of InS precipitation and the films growth under conditions of spontaneous formation of the solid phase in the solution has been studied. Formal rate law of indium(III) sulfide formation accounting for the partial orders of InS precipitation with respect to the system components and the process activation energy has been derived. The effects of the reaction mixture composition, temperature, and the synthesis duration of In2S3 films growth have been studied. [ABSTRACT FROM AUTHOR]

Ionic equilibria in the systems Zn-CHO and Zn2+-NH-OH-were analyzed and boundary conditions and formation regions of ZnS and accompanying impurity phases Zn(OH) and ZnCN were determined. The hydrochemical method was used to synthesize nanocrystalline zinc sulfide films with thicknesses of 200-240 nm. The scanning electron microscopy demonstrated the influence exerted by complexing agents, nature of a zinc salt, substrate material, and process temperature on the microstructure and morphology of the ZnS layers synthesized. The nanostructured ZnS films have a B3 cubic structure (sphalerite type, space group F433333333-m). [ABSTRACT FROM AUTHOR]

Semiconductor and photoelectric characteristics of films of solid solutions of PbSeS obtained through combined hydrochemical deposition of lead sulfide and selenide from a citrate-ammonia reaction bath by a mixture of thio- and selenocarbamide have been investigated. The effect of thermal treatment in air at (633-668) K on the composition, structure, morphology, and photosensitive characteristics of PbSeS films has been investigated. The synthesis conditions and composition of PbSeS films providing the maximum photoresponse level have been revealed. [ABSTRACT FROM AUTHOR]

Conditions of the hydrochemical synthesis of thin tellurium fi lms by reduction of an aqueous solution of tellurous acid with hydrazine were determined. The redox potentials of tellurous acid and hydrazine and their difference in relation to pH of the medium and concentration of tellurite ions were calculated. The kinetics of tellurium layer growth on glass-ceramic substrates and the structure, composition, and morphology of the layers were studied. [ABSTRACT FROM AUTHOR]

We propose a technique for wet-chemical codeposition of lead sulfide and selenide using thiourea and selenourea to form films of PbSeS substitutional solid solutions. The synthesized nanocrystalline layers with NaCl (B1) structure simultaneously contain both PbS-based and PbSe-based PbSeS solid solutions (0 < y < 0.9). [ABSTRACT FROM AUTHOR]

Photoelectric characteristics of films of the PbSnSe solid solution based on the four-layer (SnSe-PbSe) composition obtained by layer-by-layer hydrochemical synthesis with subsequent heat treatment in air within the temperature range 523-700 K are investigated. The measurements are performed in the temperature range 220-300 K. The thermal and optical band gaps, temperature coefficient of the optical band gap, dark resistance, volt-watt sensitivity, and spectral characteristics are determined. It is established that, at heat treatment temperatures below 573 K, the conductivity of the four-layer (SnSe-PbSe) compositions is characteristic of metals, while at higher temperatures, it is characteristic of p-type semiconductors. [ABSTRACT FROM AUTHOR]

The optical and dielectric characteristics of hydrochemically deposited films of lead sulfide (PbS) and supersaturated substitutional solid solutions of the PbS-ZnS system have been studied by the ellipsometry techniques. It is established that the formation of solid solutions leads to an increase in the refractive index and a decrease in the imaginary part of the complex dielectric constant as compared to those of pure PbS films. An increase in the content of ZnS in the solid solution us accompanied by a significant decrease in the dielectric loss tangent. [ABSTRACT FROM AUTHOR]

Thin films of supersaturated Zn x Pb1 − x S solid solutions containing up to 4.1 mol % ZnS have been obtained by hydrochemical deposition. The dependence of the material structure and surface morphology on the film composition has been studied. It is established that an increase in the content of zinc sulfide leads to the growth of grains with a more complicated crystalline structure, the formation of grain boundary fragments with dimensions from 60 to 100 nm, and a modification of the electrical properties of deposited layers. [ABSTRACT FROM AUTHOR]