Influence of the indium concentration on microstructural and electrical properties of proton conducting NiO-BaCe0.9-xIn xY0.1O3-δ cermet anodes for IT-SOFC application

Optimization of the major properties of anodes based on proton conductors, such as microstructure, conductivity and chemical stability, is yet to be achieved. In this study we investigated the influence of indium on the chemical stability, microstructural and electrical characteristics of proton conducting NiO-BaCe0.9-xInxY0.1O 3-δ (NiO-BCIYx) anodes. Four compositions of cermet anode substrates NiO-BCIYx were prepared using the method of evaporation and decomposition of solutions and suspensions (EDSS). Sintered anode substrates were reduced and their microstructural and electrical properties were examined before and after reduction as a function of the amount of indium. Anode substrates tested on chemical stability in the CO2 atmosphere showed high stability compared to anode substrates based on commonly used doped barium cerates. Microstructural properties of the anode pellets before and after testing in CO2 were investigated using X-ray diffraction analysis. Impedance spectroscopy measurements were used for evaluation of electrical properties of the anode pellets and the conductivity values of reduced anodes of more than 14 S cm-1 at 600 °C confirmed percolations through Ni particles. Under fuel cell operating conditions, the cell with a Ni-BCIY20 anode achieved the highest performance, demonstrating a peak power density 223 mW/cm2 at 700 °C confirming the functionality of Ni-BCIY anodes.© 2013 Elsevier B.V. All rights reserved.

Role of acidic and basic electrolytes on the structure and morphology of cathodically reduced indium tin oxide (ITO) substrates

In this report we track the structural changes suffered by ITO along galvanostatic polarization at different current densities by X-ray diffraction and SEM micrographs. The XRD shown that cathodic treatment induces structural change in ITO, characterized by appearing peaks set distinct from ITO original structure associated to metallic phase of the solid solution of In-Sn. It is interesting to note that although the different ions present in the solution are not, at least to a noticeable degree, incorporated in the metallic phase, the SEM images show that they do influence its formation, pointing to some type of adsorptive mechanism of the inert ions during the lateral diffusion of the metallic ions. © 2013 Elsevier Ltd. All rights reserved.

Optical characterization of europium-doped indium hydroxide nanocubes obtained by Microwave-Assisted Hydrothermal method

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The influence of different indium-composition profiles on the electronic structure of lens-shaped InxGa1-xAs quantum dots

We present effective-mass calculations of the bound-state energy levels of electrons confined inside lens-shaped InxGa1-xAs quantum dots (QDs) embedded in a GaAs matrix, taking into account the strain as well as the In gradient inside the QDs due to the strong In segregation and In-Ga intermixing present in the InxGa1-xAs/GaAs system. In order to perform the calculations, we used a continuum model for the strain, and the QDs and wetting layer were divided into their constituting monolayers, each one with a different In concentration, to be able to produce a specific composition profile. Our results clearly show that the introduction of such effects is very important if one desires to correctly reproduce or predict the optoelectronic properties of these nanostructures.

UV-Ozone Generation from Modified High Intensity Discharge Mercury Vapor Lamps for Treatment of Indium Tin Oxide Films

In a homemade UV-Ozone generator, different ignition tubes extracted from HID mercury vapor lamps were investigated, namely: 80, 125, 250 and 400 watts. The performance of the generator in function of the type of the ignition lamp was monitored by the measurements of the ozone concentration and the temperature increment. The results have shown that the 400 W set up presented the highest ozone production, which was used in the treatment of indium tin oxide (ITO) films. Polymer light emitting diodes were assembled using ITO films, treated for 10, 20 and 30 min, as an anode. The overall results indicate improvement of the threshold voltage (reduction) and electroluminescence of these devices.

Biodistribution of two octreotate analogs radiolabeled with indium and yttrium in rats

In this study, two octreotate derivatives N-[4-carboxy-4-[4,7,10-tris(carboxymethyl)-1,4,7,10-tetraazacyclododecane-1-yl]butanoyl]-Tyr(3)-octreotate (DOTAGA-tate) and N-[[4,10-bis(carboxymethyl)-7-(1(1,3-dicarboxypropyl))-1,4,7,10-tetraaza-cyclododec-1-yl]acetyl]-Tyr(3)-octreotate (DOTA-t-GA-tate) were radio-labeled with (111)In or (88)Y and their biodistribution profiles together with their elimination characteristics in rats were compared.

Highly improved metabolic stability and pharmacokinetics of indium-111-DOTA-gastrin conjugates for targeting of the gastrin receptor

The development of metabolically stable radiolabeled gastrin analogues with suitable pharmacokinetics is a topic of recent research activity. These imaging vectors are of interest because the gastrin/CCK2 receptor is highly overexpressed in different tumors such as medullary thyroid cancer, neuroendocrine tumors, and SCLC. The drawback of current targeting agents is either their metabolic instability or their high kidney uptake. We present the synthesis and in vitro and in vivo evaluation of 11 (111)In-labeled DOTA-conjugated peptides that differ by their spacer between the peptide and the chelate. We introduced uncharged but hydrophilic spacers such as oligoethyleneglycol, serine, and glutamine. The affinity of all radiopeptides was high with IC(50) values between 0.5 and 4.8 nM. The improvement of human serum stability is 500-fold within this series of compounds. In addition the kidney uptake could be lowered distinctly and the tumor-to-kidney ratio improved almost 60-fold if compared with radiotracers having charged spacers such as glutamic acid.

Investigation of a Method for Extraction of Indium from Zinc Flue Dust.

In metallurgical practice today some of the relatively rare metal Indium is recovered as a by-product from the ores of other metals. Indium is a soft, silvery—white metal belonging to the third group of the periodic classification. It is situated just above tin in the electrochemical series.

An Investigation into the Recovery of Indium from Fume Residue

Several months were required to produce a single gram of indium. Consequently, the industrial history of the metal is extremely short. In view of the unique properties that indium has demonstrated in this short period, it is probable that indium is still in its early stage of development. However, the commer­cial applications of the metal are well established and indium is now produced on a commercial scale. It is obtainable as the metal or in solution for electroplat­ing.

The Alloys of Gallium and Indium

Thermal analysis VIPS used to construct cooling and heating curves from which the phase diagram was determined. The data for the entire set of cooling curves were obtained by the use of mercury thermo­meters.

Indium-111 labeled gold nanoparticles for in-vivo molecular targeting.

The present report describes the synthesis and biological evaluation of a molecular imaging platform based on gold nanoparticles directly labeled with indium-111. The direct labeling approach facilitated radiolabeling with high activities while maintaining excellent stability within the biological environment. The resulting imaging platform exhibited low interference of the radiolabel with targeting molecules, which is highly desirable for in-vivo probe tracking and molecular targeted tumor imaging. The indium-111 labeled gold nanoparticles were synthesized using a simple procedure that allowed stable labeling of the nanoparticle core with various indium-111 activities. Subsequent surface modification of the particle cores with RGD-based ligands at various densities allowed for molecular targeting of the αvß3 integrin in-vitro and for molecular targeted imaging in human melanoma and glioblastoma models in-vivo. The results demonstrate the vast potential of direct labeling with radioisotopes for tracking gold nanoparticles within biological systems.

Ionization levels of doped copper indium sulfide chalcopyrites

The electronic structure of modified chalcopyrite CuInS2 has been analyzed from first principles within the density functional theory. The host chalcopyrite has been modified by introducing atomic impurities M at substitutional sites in the lattice host with M = C, Si, Ge, Sn, Ti, V, Cr, Fe, Co, Ni, Rh, and Ir. Both substitutions M for In and M for Cu have been analyzed. The gap and ionization energies are obtained as a function of the M-S displacements. It is interesting for both spintronic and optoelectronic applications because it can provide significant information with respect to the pressure effect and the nonradiative recombination.

Indium-cadmium-oxide films having exceptional electrical conductivity and optical transparency: Clues for optimizing transparent conductors

Materials with high electrical conductivity and optical transparency are needed for future flat panel display, solar energy, and other opto-electronic technologies. InxCd1-xO films having a simple cubic microstructure have been grown on amorphous glass substrates by a straightforward chemical vapor deposition process. The x = 0.05 film conductivity of 17,000 S/cm, carrier mobility of 70 cm2/Vs, and visible region optical transparency window considerably exceed the corresponding parameters for commercial indium-tin oxide. Ab initio electronic structure calculations reveal small conduction electron effective masses, a dramatic shift of the CdO band gap with doping, and a conduction band hybridization gap caused by extensive Cd 5s + In 5s mixing.

Quantum Dot-Sensitized Solar Cells Based on Directly Adsorbed Zinc Copper Indium Sulfide Colloids

Heavy metal-based quantum dots (QDs) have demonstrated to behave as efficient sensitizers in QD-sensitized solar cells (QDSSCs), as attested by the countless works and encouraging efficiencies reported so far. However, their intrinsic toxicity has arisen as a major issue for the prospects of commercialization. Here, we examine the potential of environmentally friendly zinc copper indium sulfide (ZCIS) QDs for the fabrication of liquid-junction QDSSCs by means of photoelectrochemical measurements. A straightforward approach to directly adsorb ZCIS QDs on TiO2 from a colloidal dispersion is presented. Incident photon-to-current efficiency (IPCE) spectra of sensitized photoanodes show a marked dependence on the adsorption time, with longer times leading to poorer performances. Cyclic voltammograms point to a blockage of the channels of the mesoporous TiO2 film by the agglomeration of QDs as the main reason for the decrease in efficiency. Photoanodes were also submitted to the ZnS treatment. Its effects on electron recombination with the electrolyte are analyzed through electrochemical impedance spectroscopy and photopotential measurements. The corresponding results bring out the role of the ZnS coating as a barrier layer preventing electron leakage toward the electrolyte, as argued in other QD-sensitized systems. The beneficial effect of the ZnS coating is ultimately reflected on the power conversion efficiency of complete devices, reaching values of 2 %. In a more general vein, through these findings, we aim to call the attention to the potentiality of this quaternary alloy, virtually unexplored as a light harvester for sensitized devices.