A complex oxide Ba 5 In 1.9 Y 0.1 Al 2 ZrO 13 with hexagonal perovskite structure ( a = 5.971(4) Å, с = 24.012(1) Å) is prepared for the first time. The phase is found to dissociative-absorb water from gas phase, the degree of hydration being as high as 0.39 mol Н 2 О. It was found by using IR-spectroscopy that protons are present therein as energetically nonequivalent ОН – -groups involved in hydrogen bonds of diverse strength. Isovalent yttrium-doping of the Ba 5 In 2 Al 2 ZrO 13 phase is shown not to lead to any valuable change in the oxygen-ion-conductivity as compared with the Ba 5 In 2.1 Al 2 Zr 0.9 O 12.95 acceptor doping that allows increasing the oxygen-ion-conductivity by a factor of 1.3. Both types of doping lead to increase in the proton conductivity and, as a corollary to this, an increase in the proton concentration. For these phases the degree of hydration depends on the cell parameters, hence, is determined by space availability for ОН – -groups in the barium coordination. Proton transport dominates in the Ba 5 In 2 Al 2 ZrO 13 , Ba 5 In 2.1 Al 2 Zr 0.9 O 12.95 , and Ba 5 In 1.9 Y 0.1 Al 2 ZrO 13 phases below 600 о С in humid atmosphere ( p H 2 О = 1.92 × 10 –2 atm).

Thin films of CdxPb1 – xS (0 ≤ x ≤ 0.094) substitutional solid solutions of cubic structure B1 (space group Fm) were prepared by chemical deposition and characterized by X-ray diffraction, scanning electron microscopy, EDX elemental analysis, and Raman spectroscopy. Once the cadmium sulfate concentration in the batch reached some critical value (0.1 mol/L), the films formed involved two autonomous phases: CdxPb1 – xS substitutional solid solutions and hexagonal cadmium sulfide CdyS of structure В4 (space group P63mc). The method and its parameters as proposed are efficient for manufacturing heterostructures in the CdS–PbS system in one-pot deposition.

Установлено ингибирующее действие йодида аммония NH 4 I на кинетику роста пленки сульфида свинца при варьировании его исходной концентрации в растворе в пределах 0.05–0.40 М. Введение ингибитора способствует уменьшению размеров зерен, увеличению до ~13% частиц нанодиапазона и до 3.7 ат. % йода в составе пленок PbS в зависимости от условий синтеза. По результатам рентгеновских исследований установлено, что синтезированные слои сохраняют кубическую структуру B 1 (пр. гр. \(Fm\bar {3}m\) ). При повышении концентрации ингибирующей добавки в растворе наблюдается увеличение параметра кристаллической решетки сульфида свинца от 0.59315(1) до 0.59442(3), что связано с замещением серы йодом в кристаллической решетке PbS. Максимум спектральной чувствительности и "правая" граница фотоответа пленок PbS сдвигаются в коротковолновую область – с 2.5 до 2.2 мкм и с 3.0 до 2.8 мкм соответственно, что может быть следствием образования широкозонной фазы PbI 2 . Низкотемпературными исследованиями пленок, осажденных в присутствии 0.15 и 0.25 моль/л NH 4 I, определены значения термической ширины запрещенной зоны, составившие 0.46 и 0.51 эВ при энергии активации примесных акцепторных уровней соответственно 0.135 эВ и 0.153 эВ. Легированные йодом пленки PbS имеют относительно высокую вольт-ваттную чувствительность к ИК-излучению за счет инверсии зон проводимости ( n → p ) при аномально малых значениях постоянной времени.

Ammonium iodide (NH4I) has been shown to have an inhibiting effect on the growth kinetics of lead sulfide films at initial NH4I concentrations in solution from 0.05 M to 0.40 M. The addition of the inhibitor leads to a decrease in grain size, an increase in the fraction of nanoparticles in the PbS films to similar to 13%, and an increase in the iodine content of the films to 3.7 at %, depending on growth conditions. X-ray diffraction characterization has shown that the films have a B1 cubic structure (sp. gr. Fm (3) over barm). Increasing the inhibitor concentration in solution leads to an increase in the lattice parameter of the lead sulfide from 0.59315(1) to 0.59442(3) nm, due to iodine substitution for sulfur in the PbS crystal lattice. The spectral sensitivity peak and the long-wavelength edge of the photoresponse of the PbS films shift to shorter wavelengths from 2.5 to 2.2 and from 3.0 to 2.8 mu m, respectively, which is attributable to the formation of the wide-band-gap phase PbI2. Using low-temperature measurements, the thermal band gap of the films grown in the presence of 0.15 and 0.25 mol/L NH4I has been determined to be 0.46 and 0.51 eV. The respective activation energies for acceptor impurity levels are 0.135 and 0.153 eV. The iodine-doped PbS films offer a relatively high voltage responsivity in the IR spectral region owing to an n- to p-type conversion, in combination with an anomalously short response time.

Thin films of Cd x Pb 1 – x S (0 ≤ x ≤ 0.094) substitutional solid solutions of cubic structure B 1 (space group Fm 3 m ) were prepared by chemical deposition and characterized by X-ray diffraction, scanning electron microscopy, EDX elemental analysis, and Raman spectroscopy. Once the cadmium sulfate concentration in the batch reached some critical value (0.1 mol/L), the films formed involved two autonomous phases: Cd x Pb 1 – x S substitutional solid solutions and hexagonal cadmium sulfide Cd y S of structure В 4 (space group P 6 3 mc ). The method and its parameters as proposed are efficient for manufacturing heterostructures in the CdS–PbS system in one-pot deposition.

Composites of (1-x)Gd2Zr2O7·xMgO were prepared by mixing gadolinium zirconate with freshly precipitated Mg(OH)2 followed by heat treatment at 1500 °C. Small concentrations of magnesium oxide dissolved in the complex oxide matrix of Gd2Zr2O7. This led to decrease in the lattice parameters of the matrix phase and a complex redistribution of Gd and Zr over the A and B sublattices. According to the impedance spectroscopy results of the studied samples, for (1-x)Gd2Zr2O7·xMgO (x = 0.05, 0.07, 0.10), the ionic conductivity was slightly higher than that for the undoped Gd2Zr2O7. The share of dominant ion transport did not change upon doping with magnesium oxide. The composites showed chemical resistance in a lithium halide (LiCl) melt and interacted with LiCl-xLi2O (x = 2 wt.%, 4 wt.%) melts at 650 °C with the formation of a Gd2O3 phase or a mixture of phases (Gd2O3, Li2ZrO3, ZrO2, LiGdO2, or LiGdCl2) on the ceramic surface, respectively.

A complex oxide Ba5In1.9Y0.1Al2ZrO13 with hexagonal perovskite structure (a = 5.971(4) Å, с = 24.012(1) Å) is prepared for the first time. The phase is found to dissociative-absorb water from gas phase, the degree of hydration being as high as 0.39 mol Н2О. It was found by using IR-spectroscopy that protons are present therein as energetically nonequivalent ОН–-groups involved in hydrogen bonds of diverse strength. Isovalent yttrium-doping of the Ba5In2Al2ZrO13 phase is shown not to lead to any valuable change in the oxygen-ion-conductivity as compared with the Ba5In2.1Al2Zr0.9O12.95 acceptor doping that allows increasing the oxygen-ion-conductivity by a factor of 1.3. Both types of doping lead to increase in the proton conductivity and, as a corollary to this, an increase in the proton concentration. For these phases the degree of hydration depends on the cell parameters, hence, is determined by space availability for ОН–-groups in the barium coordination. Proton transport dominates in the Ba5In2Al2ZrO13, Ba5In2.1Al2Zr0.9O12.95, and Ba5In1.9Y0.1Al2ZrO13 phases below 600оС in humid atmosphere (pH2О = 1.92 × 10–2 atm).

Polycrystalline films of Cd x Pb 1-x S (0≤ x≤0.05) substitutional solid solutions with a cubic structure B1 (Fm3m space group) containing amorphous cadmium sulfide were obtained by chemical bath deposition. Upon reaching a critical concentration of the cadmium salt in the reactor, the films consisted of substitutional solid solution and cubic CdS with the B3 structure (F43m space group). Scanning electron microscopy established the morphological features associated with the secondary nucleation and formation of the cadmium sulfide phase. The structural characteristics of the films have been calculated by a full-profile analysis of X-ray diffraction patterns. We have revealed the correlation between phase and elemental composition of Cd x Pb 1-x S/CdS films with their voltage and current photosensitivity. Based on the received data, we have assumed the role of the individual CdS phase for the photoconductivity mechanism of Cd x Pb 1-x S solid solutions. Keywords: chemical bath deposition, thin films, solid solutions, cadmium sulfide, photosensitivity, current-voltage characteristics.

Materials with pyrochlore structure A2B2O7 have attracted considerable attention owing to their various applications as catalysts, sensors, electrolytes, electrodes, and magnets due to the unique crystal structure and thermal stability. At the same time, the possibility of using such materials for electrochemical applications in salt melts has not been studied. This paper presents the new results of obtaining high-density Mg2+-doped ceramics based on Gd2Zr2O7 with pyrochlore structure and comprehensive investigation of the electrical properties and chemical stability in a lithium chloride melt with additives of various concentrations of lithium oxide, performed for the first time. The solid solution of Gd2−xMgxZr2O7−x/2 (0 ≤ x ≤ 0.10) with the pyrochlore structure was obtained by mechanically milling stoichiometric mixtures of the corresponding oxides, followed by annealing at 1500 °C. The lattice parameter changed non-linearly as a result of different mechanisms of Mg2+ incorporation into the Gd2Zr2O7 structure. At low dopant concentrations (x ≤ 0.03) some interstitial positions can be substituted by Mg2+, with further increasing Mg2+-content, the decrease in the lattice parameter occurred due to the substitution of host-ion sites with smaller dopant-ion. High-density ceramics 99% was prepared at T = 1500 °C. According to the results of the measurements of electrical conductivity as a function of oxygen partial pressure, all investigated samples were characterized by the dominant ionic type of conductivity over a wide range of pO2 (1 × 10–18 ≤ pO2 ≤ 0.21 atm) and T < 800 °C. The sample with the composition of x = 0.03 had the highest oxygen-ion conductivity (10−3 S·cm−1 at 600 °C). The investigation of chemical stability of ceramics in the melt of LiCl with 2.5 mas.% Li2O showed that the sample did not react with the melt during the exposed time of one week at the temperature of 650 °C. This result makes it possible to use these materials as oxygen activity sensors in halide melts.

The new phase Ba5In2Al2Zr0.9Nb0.1O13.05 with hexagonal perovskite structure was obtained. The substitution of Zr4+ by smaller Nb5+ was accompanied by the incorporation of the oxygen interstitials and did not lead to a significant change in the lattice parameters. It was established that the investigated sample was capable for water incorporation from the gas phase, the hydration degree value was 0.24 mol H2O. IR-spectroscopy analysis defined the presence of OH−-groups with different thermal stability, which participate in different hydrogen bonds. The new phase Ba5In2Al2Zr0.9Nb0.1O13.05 demonstrates the predominant protonic conductivity at pH2O = 2·10−2 atm and Т600 °C.

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 CrCl 3 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 NH 4 I and CrCl 3 into the reactor preserves the B 1 cubic structure of PbS and yields an increase in the band gap E g by 0.16–0.20 eV, a decrease in the dark resistance R d , and an increase in the voltage sensitivity U s . The dependences of E g and U s on the chromium-salt concentration in the reaction bath are of extreme character, with a maximum at 0.016 M of CrCl 3 , 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.

Polycrystalline films of CdxPb1−xS (0 ≤ x ≤ 0.05) substitutional solid solutions with a cubic structure B1 (Fm3 ̅m space group) containing amorphous cadmium sulfide were obtained by chemical bath deposition. Upon reaching a critical concentration of the cadmium salt in the reactor, the films consisted of substitutional solid solution and cubic CdS with the B3 structure (F43 ̅m space group). Scanning electron microscopy established the morphological features associated with the secondary nucleation and formation of the cadmium sulfide phase. The structural characteristics of the films have been calculated by a full-profile analysis of X-ray diffraction patterns. We have revealed the correlation between phase and elemental composition of CdxPb1−xS/CdS films with their voltage and current photosensitivity. Based on the received data, we have assumed the role of the individual CdS phase for the photoconductivity mechanism of CdxPb1−xS solid solutions.

The hexagonal perovskite Ba5In2Al2ZrO13 and In3+-doped phase Ba5In2.1Al2Zr0.9O12.95 were prepared by the solid-state synthesis method. The introduction of indium in the Zr-sublattice was accompanied by an increase in the unit cell parameters: a = 5.967 Å, c = 24.006 Å vs. a = 5.970 Å, c = 24.011 Å for doped phase (space group of P63/mmc). Both phases were capable of incorporating water from the gas phase. The ability of water incorporation was due to the presence of oxygen deficient blocks in the structure, and due to the introduction of oxygen vacancies during doping. According to thermogravimetric (TG) measurements the compositions of the hydrated samples corresponded to Ba5In2Al2ZrO12.7(OH)0.6 and Ba5In2.1Al2Zr0.9O12.54(OH)0.82. The presence of different types of OH−-groups in the structure, which participate in different hydrogen bonds, was confirmed by infrared (IR) investigations. The measurements of bulk conductivity by the impedance spectroscopy method showed that In3+-doping led to an increase in conductivity by 0.5 order of magnitude in wet air (pH2O = 1.92·10−2 atm); in this case, the activation energies decreased from 0.27 to 0.19 eV. The conductivity−pO2 measurements showed that both the phases were dominant proton conductors at T < 500 °C in wet conditions. The composition Ba5In2.1Al2Zr0.9O12.95 exhibited a proton conductivity ~10−4 S·cm−1 at 500 °C. The analysis of partial (O2−, H+, h•) conductivities of the investigated phases has been carried out. Both phases in dry air (pH2O = 3.5·10−5 atm) showed a mixed (oxygen-ion and hole) type of conductivity. The obtained results indicated that the investigated phases of Ba5In2Al2ZrO13 and Ba5In2.1Al2Zr0.9O12.95 might be promising proton-conducting oxides in the future applications in electrochemical devices, such as solid oxide fuel cells. Further modification of the composition and search for the optimal dopant concentrations can improve the H+-conductivity.

Chemical deposition is used to form thin-film layers of manganese-doped zinc sulfide (ZnS(Mn)) on frosted glass substrates. The films are 220 nm thick and composed of lenticular-shaped grains with sizes smaller than those of ZnS films. It is found that introducing manganese(II) chloride into the reaction mixture preserves the excess content of the metal over the content of chalcogen. Manganese in amounts of 2.5 ± 0.25 at.

The evolution of the morphology, composition, structural characteristics (lattice constant, microstrains, texturing), optical and photoelectric properties of the PbS films obtained by chemical bath deposition in the presence of ammonium iodide and chromium (III) chloride at a concentration of up to 0.02 M has been studied. According to the elemental analysis by an energy dispersive X-ray spectroscopy, the chromium content in the PbS films has a nonmonotonic dependence on the CrCl3 concentration, and the largest amount is 1.08 at%. The particle size distribution is monomodal, and the average size of the particles forming the films varies from ~ 100 to ~ 225 nm with a content of 2–6% of nanoparticles. The introduction of NH4I and CrCl3 into the reactor preserves the cubic B1 structure of lead sulfide and results in 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 concentration of the chromium salt in the reaction bath have an extreme character with a maximum at 0.016 M, which is associated with the nonmonotonic incorporation of chromium into the PbS lattice. The results of studying the current-voltage characteristics of thin-film PbS(I) and PbS(I, Cr) layers are in good agreement with the results of the structural, optical, and photosensitive properties.

The interaction between Gd2Zr2O7 and molten LiCl-Li2O (2 wt%) was studied for 24-52 h at 650-710 degrees C in an argon atmosphere. Gd2Zr2O7 is analyzed as a promising structural material for sensors used during pyrochemical reprocessing of spent nuclear fuel and for long-term storage or final disposal of high-level nuclear wastes. The chemical stability of Gd2Zr2O7 relative to the components of the LiCl-Li2O melt was thermodynamically evaluated. The surface morphology and structure of the samples before and after the experiment were analyzed using an X-ray diffractometer and scanning electron microscopy. The formation of a new Li+-doped phase based on Gd2Zr2O7 and the Gd2O3 evolution onto the material surface was revealed by the X-ray diffraction analysis (XRD). Changes in the microstructure of the samples confirm the presence of large particles in the surface layer corresponding to the Gd2O3 phase, which is in good agreement with the XRD data. A profilometer was used to measure the roughness of the ceramics. Presumably, the thickness of the lithium-doped Gd2Zr2O7 film, which is inhomogeneously distributed over the surface of the samples, was 3 mu m. Therefore, it was found that dense Gd2Zr2O7 (F) and Gd2Zr2O7 (P) ceramics can be used in LiCl-Li2O (2 wt %) as a structural material resistant to the high-temperature chemical attack.

The pyrochlore Gd1.55Li0.45Zr2O6.55 was prepared by the solution and solid-state methods. The introduction of lithium in the Gd-sublattice led to decrease in the lattice parameter a = 10.4830(8) Å in comparison with Gd2Zr2O7 (a =10.5346(2) Å). Monitoring of the lithium content in the sample during heat treatments showed a loss of lithium at temperatures above 1100 °C, so, to maintain the stoichiometry of lithium the low temperature sintering methods are required. The sample Gd1.55Li0.45Zr2O6.55 exhibited a predominant oxygen-ion transport over a wide range of temperatures. Although doping did not lead to an increase in the oxygen-ion conductivity compared to Gd2Zr2O7, it caused the suppression of the hole conductivity.

The calculating of ionic equilibria in the system «Pb(CH3COO)2 - CdCl2 - Na3C6H5O7 - ‎(NH3)2(CH2)2 - N2H4CS» allowed us to find conditions and concentration regions of PbS and CdS co-deposition. The determined conditions provided the CBD obtaining of CdxPb1−xS (0 ≤ x ≤ 0.033) substitutional solid solutions films with a cubic structure B1 (space group Fm ) with the grains preferred orientation (200). We established the evolution of the surface morphology of the synthesized films from cubic crystallites to hierarchical structure of globular aggregates by scanning electron microscopy. A quantitative analysis of diffraction patterns showed a decrease of microstrains in CdxPb1−xS films by a about factor of 3 with an increase of the cadmium chloride concentration in the reaction mixture from 0.005 to 0.14 mol/l. The excess of the cadmium content, established by EDX analysis, in the studied films as compared to its content in the solid solution is associated with the additional formation of the amorphous CdS phase up to 72 mol %. A Corrigendum is available for this article at https://doi.org/10.15826/chimtech.2021.8.2.12.