Incorporation Of In3 Research Articles

Pure SnSe, In and Sb doped SnSe single crystals – Growth, structural, surface morphology and optical bandgap study

The pure SnSe is a potential material for technological applications due to its favourable electrical, optical, thermal, etc. properties. To make SnSe more suitable for varied applications needs tailoring of properties. In this work, an effort has been made to modify the properties of SnSe by doping with group III (indium) and V (antimony) elements of the periodic table. The pure SnSe, indium (In) and antimony (Sb) doped SnSe single crystals are grown by direct vapour transport technique. Two concentrations of 5% and 10% are employed for doping. The chemical compositions of the grown crystals are confirmed by X-ray energy dispersive and electron probe micro analysis techniques. The X-ray diffraction analysis substantiated the orthorhombic SnSe phase of all grown single crystals. The surface morphology study of the as-grown single crystal surfaces showed the crystal growth to have occurred by layer growth mechanism. The hot point probe technique analysis showed all crystals to be p-type semiconducting in nature. The optical absorption spectra of all as-grown samples showed sharp absorption near 846 nm wavelength. The modification of the optical bandgaps by incorporation of In3+ and Sb3+ ions within SnSe is studied. The obtained results are discussed in details.

Impact of indium substitution on dielectric and magnetic properties of Cu0.5Ni0.5Fe2-xO4 ferrite materials

Indium substituted CuNi nanoferrites with nominal compositions Cu0.5Ni0.5InxFe2-xO4 (x = 0.00–0.32) were successfully synthesized by sol-gel auto ignition method. X-ray diffraction patterns illustrated the single phase spinel structure for x ≤ 0.24. The lattice parameter ‘a’ increased from 8.3349 to 8.3723 Å and then it decreased for x = 0.32. X-ray density increased from 5.43 to 5.79 g/cm3. The average crystallite sizes lie in the range 33.21–17.78 nm. The cell volume was increased from 579.03 to 586.86 Å3 with the substitution of indium ions into the spinel lattice of copper nickel ferrites. The compositional dependence of tetrahedral and octahedral radii was explained on the basis of lattice parameter. The incorporation of In3+ ions in copper nickel ferrites exhibited the decreased in bulk density. The dielectric parameters were explained over entire range of frequency (1M-3 GHz). The dielectric parameters i.e dielectric constant, dielectric loss and tan loss were found to decrease with the increase of indium concentration. The saturation magnetization (Ms) and Bohr magneton (nB) first increased and then decreased. The remanence (MR) was increased with the substitution of indium ions. The coercivity and anisotropy constant were decreased which might be due to weak A-B super exchange interaction. The results of magnetic and dielectric properties suggested that In3+ substituted copper nickel ferries are suitable for high frequency applications.

Indium doping effect on properties of ZnO nanoparticles synthesized by sol–gel method* *Project supported by the Deanship of Academic Research at Imam Mohamed Ibn Saud Islamic University (IMSIU), Riyadh, Kingdom of Saudi Arabia, (Research Project Nos. 381212 and 1438H).

Pure ZnO and indium-doped ZnO (In–ZO) nanoparticles with concentrations of In ranging from 0 to 5% are synthesized by a sol–gel processing technique. The structural and optical properties of ZnO and In–ZO nanoparticles are characterized by different techniques. The structural study confirms the presence of hexagonal wurtzite phase and indicates the incorporation of In3+ ions at the Zn2+ sites. However, the optical study shows a high absorption in the UV range and an important reflectance in the visible range. The optical band gap of In–ZnO sample varies between 3.16 eV and 3.22 eV. The photoluminescence (PL) analysis reveals that two emission peaks appear: one is located at 381 nm corresponding to the near-band-edge (NBE) and the other is observed in the green region. The aim of this work is to study the effect of indium doping on the structural, morphological, and optical properties of ZnO nanoparticles.

Crystallization features and physico-chemical properties of alkali and alkaline aluminoborate glass–ceramics

Preparation and characterization of glass–ceramics based on CaO–Al2O3–B2O3 system, modified by replacing CaO by different alkali and alkaline earth oxides, and In2O3/Al2O3 substitustion were implemented. Different crystalline phases, including β-CaAl2B2O7, Na2Al2B2O7, LiAl5O8, Li4Al4B6O17, Li2AlBO4, SrAl2B2O7, BaAl2B2O7, α-(Ca1-x,Inx)Al2B2O7, and InBO3, were developed from the heat-treated glasses. The incorporation of In3+ in the position of Ca2+ in β-CaAl2B2O7 crystal lattice was responsible for phase transition of β-CaAl2B2O7 to α-CaAl2B2O7 phase. The coefficient of thermal expansion CTE of prepared glass–ceramics was between −65 × 10−7 and 72 × 10−7 K−1 in the temperature range from 25 to 600 °C. The glass–ceramic specimens containing XAl2B2O7 as the principal crystalline phase were characterized by negative CTE values. In contrast, the replacement of CaO in the base glass by alkali oxides like Na2O and Li2O led to a dramatic transformation of the negative CTE to postive values. The complete replacement of calcium oxide in the base glass by various alkali and alkaline earth oxides markedly decreased the chemical durability of the investigated glass–ceramic specimens, while substitution of Al2O3 by In2O3 resulted in improving the chemical stability of the crystalline samples. The density of the glass specimens were found to be within the range 2.35–3.38 g/cm3, while the density of the glass–ceramic samples was in the range of 2.37–3.13 g/cm3.

Controlling the Properties of Manganese-Zinc Ferrites by Substituting In3+ and Al3+ Ions

The effect of substitution of In3+ and Al3+ ions on the electrical and magnetic properties of Mn-Zn ferrites has been investigated. The substitution of In3+ ions for Fe3+ ions resulted in an increase of lattice parameter, owing to the larger size of In3+ ions, whereas lattice parameter was found to decrease on substituting Al3+ ions in place of the Fe3+ ions, owing to the smaller size of Al3+ ions. The dc resistivity was found to increase with the substitution of In3+ and Al3+ ions in the Mn-Zn ferrite system. The improvement in the dc resistivity has been observed at the expense of deterioration in the magnetic properties of Al3+ substituted Mn-Zn ferrites. A significant reduction in the values of initial permeability, saturation magnetization and Curie temperature was observed with successive increase of Al3+ ions. The saturation magnetization and initial permeability were found to increase with incorporation of In3+ ions. A marked increase in the value of initial permeability was found for the Mn0.4Zn0.6In0.5Fe1.5O4 ferrite. Curie temperature was found to decrease with an increase of In3+ ion concentration. These changes in the properties are explained on the basis of their magnetic interactions, a modified cation distribution and various models.

Synthesis, characterization, and catalytic activity in the n-heptane conversion over Pt/In–Al2O3 sol–gel prepared catalysts

Platinum catalysts supported on indium-doped alumina were prepared by the sol–gel method. The method allows the incorporation of In3+ in the alumina network. The indium-doped alumina supports showed narrow pore size distribution (5.4–4.0 nm) and high specific surface areas (258–280 m2/g). The 27Al NMR-MAS spectroscopy identified aluminum in tetrahedral, pentahedral, and octahedral coordination; however, the intensity of the signal assigned to aluminum in pentahedral coordination diminishes with the increase of the content of indium. Total acidity determined by ammonia thermodesorption diminishes strongly in Pt/In–Al2O3 catalysts, suggesting a selective deposit of platinum over the acid sites of the support. The effect of the support in the platinum catalytic activity was evaluated in the n-heptane dehydrocyclization reaction. The selectivity patterns for such reaction were modified substantially in the doped Pt/In–Al2O3 catalysts, in comparison with the Pt-In/Al2O3–I coimpregnated reference catalyst. As an important result, the formation of benzene was suppressed totally over the indium-doped alumina sol–gel supports with a high content (3 wt%) of indium.

Effect of substitution of In3+ ions on the electrical and magnetic properties and m�ssbauer study of Mg0.9Mn0.1In x Fe2?x O4 ferrites

The effect of substitution of diamagnetic In3+ ions on the electrical and magnetic properties of Mg-Mn ferrites was studied in the ferrite series Mg0.9Mn0.1 In x Fe2−x O4 wherex varied from 0–0.8 in steps of 0.1. The incorporation of In3+ ions in place of Fe3+ ions resulted in an increase of lattice parameter owing to the larger size of the substituted ions, and an increase of d.c. resistivity owing to reduction of Verwey's hopping mechanism. It also resulted in improvement of saturation magnetization and produced a marked increase in the value of initial permeability, thus upgrading the bulk magnetic properties of these ferrites. These bulk magnetic properties improve due to substitution of diamagnetic In3+ ions,x, up to 0.5 only, whereas they deteriorate for a higher content of In3+ ions. The variations of saturation magnetization have been explained on the basis of modified cation distribution and their magnetic interactions. A large increase in the value of initial permeability has been attributed to its dependence onM s and magnetocrystalline anisotropy constant. A comparison of bulk magnetic properties with the inferences drawn from Mossbauer studies of these samples shows a similar trend. It is concluded that the substitution of In3+ ions,x, up to 0.5 in Mg-Mn ferrites results in the production of a hyperfine field at A as well as B sites, followed by ferromagnetic relaxation and paramagnetic transition for higher concentrations of In3+ ions. These variations have been explained on the basis of the effect produced by In3+ ions on the magnetic interactions, supertransferred hyperfine fields and domain-wall oscillations.