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1.
Highly crystalline and monodisperse In2O3 nanoparticles were successfully prepared by thermal decomposition of In(dipy)3Cl3·2H2O in oleylamine and oleic acid under inert atmosphere. The size of In2O3 nanoparticles could be readily tuned from 10–15 nm to 40–50 nm, depending on the molar ratio of precursor to combined solvent in the reaction system. As‐synthesized In2O3 nanoparticles have a center‐body cubic structure as characterized by powder X‐ray diffraction and selected‐area electron diffraction. Transmission electron microscopy images showed that In2O3 nanoparticles have a narrow size distribution. A relatively strongly PL peak centered at 378 nm could be clearly seen when 10–15 nm In2O3 nanoparticles redispersed in cyclohexane were excited at 275 nm at room temperature. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

2.
Chemical Transport of Solid Solutions. 8. Transport Phenomena and Ionic Conductivity in the In2O3/SnO2 System Chemical transport reactions are a suitable pathway to the preparation of In2O3‐rich and SnO2‐rich mixed crystals coexisting in the In2O3/SnO2 system (Cl2 as transport agent, 1050 → 900 °C). Experiments are consistent with thermodynamic calculations. The existence of other phases in the system In2O3/SnO2 could not be confirmed. The ionic conductivity of In2O3(SnO2) was investigated.  相似文献   

3.
As a conceptual study, In0 nanoparticles are obtained by NaBH4‐driven reduction of InCl3 · 4H2O and transferred from a polar/hydrophilic diethylene glycol phase to a non‐polar hydrophobic dodecane phase for purification and stabilization. Finally, the In0 nanoparticles are oxidized via a Laux‐like reaction with nitrobenzene to In2O3 nanoparticles. The challenge of the reaction is to perform the final oxidation to In2O3 under mild conditions with the colloidal stability, particle size and particle size distribution of the initial In0 nanoparticles retained. To this concern, the mean diameter of the initial In0 nanoparticles changed from 11(1) to 14(2) nm of the oxidized In2O3 nanoparticles. Such multi‐step reaction, including reduction, nucleation, phase transfer, exchange of surface capping and oxidation are of increasing importance for nanoparticles. Especially, Laux‐type conditions with nitrobenzene as a molecular oxidizing agent of nanoparticles have not been used till now. Particle size, size distribution and chemical composition of the In0 and In2O3 nanoparticles are analyzed by DLS, SEM, XRD, FT‐IR and HRTEM.  相似文献   

4.
We fabricated films of cubic indium oxide (In2O3) by chemical bath deposition (CBD) for solar water splitting. The fabricated films were characterized by X‐ray diffraction analysis, Raman scattering, X‐ray photoelectron spectroscopy, and scanning electron microscopy, and the three‐dimensional microstructure of the In2O3 cubes was elucidated. The CBD deposition time was varied, to study its effect on the growth of the In2O3 microcubes. The optimal deposition time was determined to be 24 h, and the corresponding film exhibited a photocurrent density of 0.55 mA cm?2. Finally, the film stability was tested by illuminating the films with light from an AM 1.5 filter with an intensity of 100 mW cm?2.  相似文献   

5.
The local structure of In2O3 cosubstituted with Zn and Sn (In2−2xSnxZnxO3, x≤0.4 or ZITO) was determined by extended X-ray absorption fine structure (EXAFS) for x=0.1, 0.2, 0.3 and 0.4. The host bixbyite In2O3 structure is maintained up to the enhanced substitution limit (x=0.4). The EXAFS spectra are consistent with random substitution of In by the smaller Zn and Sn cations, a result that is consistent with the “good-to-excellent” conductivities reported for ZITO.  相似文献   

6.
On the Crystal Structure of Ba3In2Zn5O11. An Oxoindate/zincatesol;zincate with Zn10O20 and In4O16 Macropolyhedra with Zn2+ in Tetrahedral Coordination by O2? Ba3In2Zn5O11 was prepared for the first time by a flux technique and investigated by single crystal X-ray work. It crystallizes with cubic symmetry, space group T-F4 3m, a = 13.3588 Å, Z = 8. Zn2+ show tetrahedral coordination by O2?, forming Zn10O20 macropolyhedra. In addition the nZn/Osol;O part of the crystal structure is made up of Zn10O20 parts. Edge connection of four InO6 octahedra results in In4O16 groups. The crystal structure will be shown and discussed.  相似文献   

7.
Contributions on Crystal Chemistry and Thermal Behaviour of Anhydrous Phosphates. XXXIII [1] In2P2O7 an Indium(I)‐diphosphatoindate(III), and In4(P2O7)3 — Synthesis, Crystallization, and Crystal Structure Solid state reactions via the gas phase lead to the new mixed‐valence indium(I, III)‐diphosphate In2P2O7. Colourless single crystals of In2P2O7 have been grown by isothermal heating of stoichiometric amounts of InPO4 and InP (800 °C; 7d) using iodine as mineralizer. The structure of In2P2O7 [P21/c, a = 7.550(1) Å, b = 10.412(1) Å, c = 8.461(2) Å, b = 105.82(1)°, 2813 independent reflections, 101 parameter, R1 = 0.031, wR2 = 0.078] is the first example for an In+ cation in pure oxygen coordination. Observed distances d(InI‐O) are exceptionally long (dmin(InI‐O) = 2.82 Å) and support assumption of mainly s‐character for the lone‐pair at the In+ ion. Single crystals of In4(P2O7)3 were grown by chemical vapour transport experiments in a temperature gradient (1000 → 900 °C) using P/I mixtures as transport agent. In contrast to the isostructural diphosphates M4(P2O7)3 (M = V, Cr, Fe) monoclinic instead of orthorhombic symmetry has been found for In4(P2O7)3 [P21/a, a = 13.248(3) Å, b = 9.758(1) Å, c = 13.442(2) Å, b = 108.94(1)°, 7221 independent reflexes, 281 parameter, R1 = 0.027, wR2 = 0.067].  相似文献   

8.
Metal oxide semiconductors(MOS)-reduced graphene oxide(rGO) nanocomposites have attracted great attention for room-tempe rature gas sensing applications.The development of novel sensing materials is the key issue for the effective detection of ammoniagas at room temperature.In the present work,the novel reduced graphene oxide(rGO)-In2 O3 nanocubes hybrid materials have been prepared via a simple electrostatic self-assembly strategy.Characterization re sults exhibit that the...  相似文献   

9.
采用溶胶凝胶法制备了In20rCdln2O4和CdO-Cdln2O4纳米复合氧化物,利用扫描电子显微镜(SEM)和X射线衍射仪(XRD)对复合材料的形貌和结构进行表征,并对其进行了乙醇、丙酮等多种气体的气敏性能测试.结果表明Cdln2O4材料复合h12O3和CdO后显著提高了对丙酮和乙醇气体的灵敏度和选择性.  相似文献   

10.
In this paper, we presented a simple and effective solution route to deposit Pt nanoparticles on electrospun In2O3 nanofibers for H2S gas detection. The morphology and chemical structure of the as-prepared samples were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectra (XPS). The results showed that large quantities of In2O3 nanofibers with diameters about from 60 to 100 nm were obtained and the surface of them was decorated with Pt nanoparticles (5–10 nm in size). The In2O3 nanofibers decorated by Pt nanoparticles exhibited excellent gas sensing properties to H2S, such as high sensitivity, good selectivity and fast response at relatively low temperature.  相似文献   

11.
A new approach is presented for preparing In2O3 thin films starting from inorganic precursors, based on a very simple but effective modification of the usual precipitation-peptization process. Indium nitrate was dissolved in methanol and In3+ ions were chelated with acetylacetone before adding concentrated base to the resulting solution. Such a route allowed obtaining long-term stable sols, from which films could be deposited on glass substrates by spin-coating. Furthermore, the films exhibited a very good adhesion and uniformity, without any need for adding additives to the solution. The modification of the In precursor was confirmed by thermal analysis, while XRD studies revealed that the films prepared with the modified route result in smaller In2O3 grains compared to the traditional precipitation-peptization process. Optical reflectance measurements on the films further highlighted the difference between the two processes. Gas-sensing tests carried out on the films deposited onto alumina substrates in the temperature range between 100 and 400°C showed that faster responses are obtained at temperatures higher than 250°C. The response value (R/R 0, where R is the electrical resistance of the sensor in the test gas and R 0 that in dry air) to 100 ppb ozone is remarkably high: it is equal to 1500 for In2O3 with a response time of about 1 minute. The recovery time is about 10 minutes.  相似文献   

12.
Chemical Vapor Transport of Solid Solutions. 11 Mixed Phases and Chemical Vapor Transport in the Systems CrIII/InIII/GeIV/O, GaIII/InIII/GeIV/O, MnIII/InIII/GeIV/O und FeIII/InIII/GeIV/O By means of chemical vapor transport methods the following mixed phases have been prepared: Cr0, 18In1, 82Ge2O7 (Cl2, 950 → 850 °C), (Ga0, 6In1, 4)2Ge2O7 (Thortveitit‐type, Cl2, 1050 → 950 °C), (Ga1, 9In0, 1)2Ge2O7 (Ga2Ge2O7‐type, 1050 → 950 °C), (In1, 9Mn0, 1)2Ge2O7 (Thortveiti‐type, Cl2, 1000 → 800 °C), mixed phase crystallizing in the Mn2Ge2O7‐structure showing a composition near MnInGe2O7 (Cl2, 1000 → 800 °C), Mn6, 5In0, 5GeO12 (Braunit‐type, Cl2, 1000 → 800 °C), (FexIn1‐x)Ge2O7 (Thortveitit‐type with x = 0…0, 94; Cl2, 840 → 780 °C). Changing the compositions of the starting materials showed no effect on the composition of the deposit except for the system Fe2O3‐In2O3‐GeO2.  相似文献   

13.
SnO2, In2O3, and Sn-doped In2O3 (ITO)/polymer and the corresponding carbon composite hollow colloids are template synthesized. It is essential that the sulfonated gel shell of the cross-linked polystyrene hollow colloid can favorably induce adsorption of target precursors. After being calcined in air to remove the template, SnO2, In2O3, and ITO hollow colloids are obtained. Because the cross-linked polymer gel can be transformed into carbon in nitrogen at higher temperature such as 800 °C, metal oxide/carbon hollow colloids are consequently derived, whose shells are mesoporous. The SnO2-, In2O3-, and ITO-containing polymer or carbon composite hollow colloids will be promising in sensors, catalysts, and fuel cells as electrode materials. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

14.
Tetrahedral Polycations [In5]7+ in ‘‘Na23In5O15”︁”︁ (=Na24In5O15?) an Unusual Oxidation Product of the Alloy NaIn The already published, red-transparent, air sensitive, cubic compound Na24In5O15 (a = 1107.7 pm, Z = 2, I43m) is an intermediate oxidation product of the intermetallic phase NaIn. It is reinvestigated with respect to the question whether it contains the tetrahedral polycation [InIn4]6+ or [InIn4]7+. In the latter case the chemical composition would be Na23In5O15 instead of Na24In5O15 and the polycation would be in accordance with the Zintl-Klemm concept. Na24In5O15 is prepared in single phased samples for the first time and investigated by means of the Rietveld refinement technique of X-ray powder data. Based on the results of the Rietveld refinements and new single crystal data in comparison to the published values we note anomalies in the occupancies of the Na positions and a pronounced anisotropy in the thermal parameters of one oxygen position. These investigations together with results obtained by analytical scanning electron microscopy, Extended Hückel and MAPLE calculations give strong evidence for the assumption of [InIn4]7+ instead of [InIn4]6+ and the associated correct composition Na23In5O15. The problems of a reliable characterization of this unique compound are discussed.  相似文献   

15.
A nano‐crystalline In2O3 was synthesized using calcinations methods and was used as a photocatalyst to degrade sulfan blue (SB) dye. In addition, this study addresses the conditions of the degradation and the factors that influenced the catalysis. In2O3 was prepared by calcining In(OH)3 at heat ranges of 100–700 °C for 24 h. The In2O3 was characterized using field emission scanning electron microscopy (FE‐SEM), an X‐ray diffractometer (XRD), thermogravimetric analysis (TGA), and high‐resolution X‐ray photoelectron spectroscopy (HR‐XPS). The activities of these samples were tested for the photocatalytic degradation of SB dye. The results indicated that the In(OH)3 that was calcined at 300 °C for 24 h had the best performance.  相似文献   

16.
Explorative solid‐state chemistry led to the discovery of the two new compounds Ga5B12O25(OH) and In5B12O25(OH). Extreme synthetic conditions within the range of 12 GPa and a temperature of 1450 °C realized in a Walker‐type multianvil apparatus resulted in the formation of an unprecedented tetragonal structure with the exclusive presence of condensed BO4 tetrahedra, forming cuboctahedral cavities. Doping of these cavities with Eu3+ in In5B12O25(OH) yielded in an orange–red luminescence. Photocatalytic tests of In5B12O25(OH) revealed a hydrogen production rate comparable to TiO2 but completely co‐catalyst free.  相似文献   

17.
NiS (nickel sulfide)–In2O3 (indium oxide) nanostructures and NiS–In2O3 decorated on graphene oxide (GO) were demonstrated by ultrasonic/hydrothermal method. The structural study demonstrates the preparation of bixbyite and hexagonal phase of In2O3 and NiS for all of the synthesized catalysts. The band gap of the synthesized catalyst was determined to be in the range of 2.30–3.00 eV. A morphological evaluation by field emission scanning electron microscopy of NiS–In2O3 decorated on graphene oxide shows support for the NiS–In2O3 on the graphene oxide layer. Different test parameters were performed to study the phase and morphology. The particle sizes of the In2O3, NiS–In2O3 and NiS–In2O3/GO nanocomposites were 56.0, 62.0 and 66.0 nm, respectively. The photocatalytic performance of NiS–In2O3/GO nanocomposites was examined for the degradation of methylene blue dye under a UV lamp. The prepared sample shows 98.25% photocatalytic degradation within 40 min and at pH 9. With the presence the NiS and GO, the photo-degradation capacities of In2O3 and NiS–In2O3 are improved owing to the low band gap being calculated in UV–vis DRS analysis. The high ratio of NiS causes the highest photocatalytic properties of NiS–In2O3 nanocomposites owing to the enhancement of charge separation efficiency and generation of hydroxyl radicals. This study presents a facile and low-cost method to prepare highly active NiS–In2O3/GO nanocomposites. The antibacterial data indicate the significant properties of NiS–In2O3/GO nanocomposites for this study.  相似文献   

18.
Multilayered heterostructures comprising of In2O3, SnO2, and Al2O3 were studied for their application in thin-film transistors (TFT). The compositional influence of tin oxide on the properties of the thin-film, as well as on the TFT characteristics is investigated. The heterostructures are fabricated by atomic layer deposition (ALD) at 200 °C, employing trimethylindium (TMI), tetrakis(dimethylamino)tin (TDMASn), trimethylaluminum (TMA), and water as precursors. After post-deposition annealing at 400 °C the thin-films are found to be amorphous, however, they show a discrete layer structure of the individual oxides of uniform film thickness and high optical transparency in the visible region. Incorporation of only two monolayers of Al2O3 in the active semiconducting layer the formation of oxygen vacancies can be effectively suppressed, resulting in an improved semiconducting and switching behavior. The heterostacks comprising of In2O3/SnO2/Al2O3 are incorporated into TFT devices, exhibiting a saturation field-effect mobility (μsat) of 2.0 cm2 ⋅ V−1 s−1, a threshold-voltage (Vth) of 8.6 V, a high current on/off ratio (IOn/IOff) of 1.0×107, and a subthreshold swing (SS) of 485 mV ⋅ dec−1. The stability of the TFT under illumination is also altered to a significant extent. A change in the transfer characteristic towards conductive behavior is evident when illuminated with light of an energy of 3.1 eV (400 nm).  相似文献   

19.
A number of sensing systems based on indium oxide doped with various metal oxides (In2O3 · WO3, In2O3 · ZnO, In2O3 · RuO2, In2O3 · Gd2O3, and In2O3 · Sm2O3) in amounts of no more than 3–5 mol % and also Au · In2O3 films were studied as sensors for detecting NO2 in air. The working temperature of sensors was 250°C (except for In2O3 · RuO2, for which T = 150–190°C). In2O3 · WO3-based sensors reach a high sensitivity especially at a concentration of NO2 in air higher than 10 ppm (the relative sensor conductivity changes by 2.5 orders of magnitude). However, a shortcoming of this system is an increased response time (7–9 min) as compared to the other studied systems, for which the response time does not exceed 15–20 s. In2O3 · Gd2O3 and In2O3 · Sm2O3 films exhibit the best sensing properties in sensitivity, selectivity, and stability. Various NO2 species adsorbed on the surface of dispersed indium oxide were detected by Fourier-transform IR spectroscopy. The mechanism of changing the conductivity of In2O3 · Gd2O3 films upon detecting NO2 in air is discussed.  相似文献   

20.
Cd-doped In2O3 was synthesized by a facile solvothermal, template-free preparation method. The phase structure and properties were characterized by various methods. The surface of Cd-doped In2O3 became coarse compared with that of pure In2O3, according to the scanning electron microscopeimages, which enhanced the ability to absorb the gas. The electron paramagnetic resonance showed that the Cd-doped In2O3 can generate more defects and oxygen vacancies. By measuring the gas sensitivity, the response of Cd-doped In2O3 was 1.6 times than that of pure In2O3. Thus, Cd-doped In2O3 can promote gas-sensing performance compared with pure In2O3.  相似文献   

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