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Two C3-symmetric ligands, 4,4′,4″-[1,3,5-benzenetriyltris(carbonylimino)]trisbenzoic acid (H3BTA) and benzene-1,3,5-trisbenzoic acid (H3BTB), were used to coordinate Er(III) and In(III). Reactions of the two C3-symmetric ligands with Er(NO3)3·6H2O and In(NO3)2·3H2O under solvothermal conditions resulted in formation of two new three-dimensional porous coordination polymers, [Er(BTA)(DMF)](DMF)2(H2O) (1) and [In(H2O)(BTB)](DMF)2 (2). In addition, in vitro anticancer activities of 1 and 2 on three human glioma cells (SHG-44, SWO-38, and TJ905) were determined. [ABSTRACT FROM AUTHOR]

The dependence of the structure of (TiZrHf)N coatings deposited by reactive magnetron sputtering on different working pressures and their mechanical and electro-optical properties were investigated. The increased working pressure contributed to the decreased oxygen contamination. With increased working pressure, the compressive stress was transitioned to tensile one. Compressively stressed coatings consisted of tightly packed columns with a smooth surface. The tensile stressed coatings presented void network structure surrounding the columnar grains with a rough surface. Moreover, the grain size initially increased and subsequently decreased. Accordingly, the (TiZrHf)N coatings deposited at high working pressure were characterized with poor hardness, low electrical conductivity, and low light reflectivity due to the porous structure and high oxygen contamination. In addition, the coating color changed from bright gold to dark gray. In this study, the working pressure was proven a sensitive deposition parameter in controlling the microstructure, mechanical, and electro-optical properties of the coating. The wide structural variation in the (TiZrHf)N coatings allowed a diverse physical performance suitable for a broad range of applications. [ABSTRACT FROM AUTHOR]

Indium zinc oxide (IZO) films were grown by direct current magnetron sputtering from vacuum hot-pressed ceramic oxide targets of In 2 O 3 :ZnO with a weight ratio of 7:3 onto glass substrates. No external heating of the substrate was used during deposition. The thickness dependences of the structural, optical, and electrical properties of IZO films were characterized. The IZO film structure remained amorphous with low roughness as its thickness increased but showed an increased degree of short-range order. The thick IZO film contained relatively high carrier concentration and mobility but exhibited low transmittance in the visible region and high reflectance in the IR region. The smallest electrical resistivity was 5.44 × 10 −4 Ω-cm for the 800 nm-thick IZO film. The optical band gap shifted to a higher energy with thickness as the carrier concentration and Urbach energy increased. An inverse linear relation was found between band gap energy and Urbach energy. In consideration of the figure of merit values, the optimized thickness of the IZO film was 800 nm due to the effect of IZO film thickness on sheet resistance. Given its low temperature process and good optoelectronic properties, the IZO film has a wide range of potential applications in various optoelectronic devices. [ABSTRACT FROM AUTHOR]

Herein, we report on the syntheses, crystal structures, and optical properties of two new selenidostannates, namely, [Emim] 5 [Sn 3 Se 7 ] 2 Cl ( 1 , Emim = 1-ethyl-3-methylimidazolium) and [Bzmim] 2 [Sn 3 Se 7 ] ( 2 , Bzmim = 1-benzyl-3-methylimidazolium). The ionic liquids (ILs) of [Emim]Cl with a short ethyl chain and [Bzmim]Cl with a bulky substituent benzyl group were used in the syntheses of compounds 1 and 2 , respectively. Although both the structures feature an anionic lamellar [Sn 3 Se 7 ] n 2 n – layer, the packing of the layers are dramatically different; such structural diversity may be ascribed to the difference of structure-directing cations incorporated in between the layers, that is [(Emim) 3 Cl] 2+ aggregates in 1 and bulky [Bzmim] + in 2 , respectively. [ABSTRACT FROM AUTHOR]

Cu–Cr–O films were prepared by DC magnetron co-sputtering using Cu and Cr targets on quartz substrates. The films were then annealed at temperatures ranging from 400 °C to 900 °C for 2 h under a controlled Ar atmosphere. The as-deposited and 400 °C-annealed films were amorphous, semi-transparent, and insulated. After annealing at 500 °C, the Cu–Cr–O films contained a mixture of monoclinic CuO and spinel CuCr 2 O 4 phases. Annealing at 600 °C led to the formation of delafossite CuCrO 2 phases. When the annealing was further increased to temperatures above 700 °C, the films exhibited a pure delafossite CuCrO 2 phase. The crystallinity and grain size also increased with the annealing temperature. The formation of the delafossite CuCrO 2 phase during post-annealing processing was in good agreement with thermodynamics. The optimum conductivity and transparency were achieved for the film annealed at approximately 700 °C with a figure of merit of 1.51×10 −8 Ω −1 (i.e., electrical resistivity of up to 5.13 Ω-cm and visible light transmittance of up to 58.3%). The lower formation temperature and superior properties of CuCrO 2 found in this study indicated the higher potential of this material for practical applications compared to CuAlO 2 . [ABSTRACT FROM AUTHOR]

Within the frame of this work, reactive magnetron-sputtered (TiZrHf)N coatings were deposited on Si substrates. The depositions were carried out from a pure TiZrHf target with varying N 2 -to-total (N 2 +Ar) flow ratios, R N . The TiZrHf alloy and its nitride coatings exhibited body-centered cubic and face-centered cubic crystal structures, respectively. The increase in R N contributed to the decrease in O 2 contamination. For nitrides, with increasing R N , the grain size decreased to a nano-sized level. Consequently, the microstructure of the nitride coatings was converted from a large columnar structure with rough surface to a fine columnar structure with a smooth surface. Moreover, the compressive stress and the corresponding lattice parameter increased initially and then decreased. The golden-like (TiZrHf)N coatings deposited at R N =20% exhibited the highest hardness of 40.7 GPa, which attained the superhard grade. Meanwhile, low electrical resistivity of 129.2 μΩ-cm and high reflectivity at 0.62 eV of 84.0% were obtained. The electro-optical behavior of (TiZrHf)N coatings was demonstrated further by spectroscopic ellipsometry on the basis of their dielectric function and energy loss function. The gold-colored (TiZrHf)N coating with excellent physical properties has a wide range of diverse potential industrial applications. [ABSTRACT FROM AUTHOR]

We investigated the effects of sputtering power on the microstructure of direct-current magnetron sputter-deposited TiVCr films on silicon wafer grown at room temperature. When the sputtering power was 100 W, composite structure with amorphous and body-centered cubic (BCC) crystal phases can be observed. When sputtering power was increased to 200 W, the composite structure was almost transformed into crystal columnar structure. Apart from interface region, the amorphous zone was composed of bundles of fine fibrous structure, whereas the BCC crystal zone contained V-shaped columnar structures without significant element segregation. Results indicated that the high sputtering power favored the formation of crystal films and the decrease of intracolumnar voids. However, a significant crack occurred, thereby widening intercolumnar voids. The film deposited at high sputtering power demonstrates slight improvement of mechanical properties. [ABSTRACT FROM AUTHOR]

Various (AlCrMoTaTi)-Si x -N coatings were prepared on Si substrates through a reactive magnetron sputtering system to methodically investigate the effects of Si contents and free Si on oxidation behavior. The as-deposited Si-containing coating presented a relatively dense and compact structure compared with the Si-free coating. An oxide layer was formed on the coating surface and continued to thicken when the coatings were exposed to ambient air at elevated temperatures. At 1073 K, a two-layer structure, which consists of an amorphous Al 2 O 3 layer with traces of other target elements followed by a rutile TiO 2 + oxide of the target element mixed zone, was developed in the oxide layer. Oxidation resistance was gradually enhanced with the continued increase in Si concentration in the coatings. At 1173 K, the coatings with Si content of as low as 7.51 at.% exhibited a single order of magnitude lower oxidation rate than that of the Si-free coating. Nanohardness measurement of the coatings further confirmed the oxidation behavior. The significantly enhanced oxidation resistance may be attributed to the presence of Al and Si in the coatings. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of discharge power on the composition and the microstructural, mechanical, and electro-optical properties of (TiZrHf)N coatings. The coatings were deposited on Si substrates via reactive magnetron sputtering. The coatings were deposited at varying discharge powers (50–300 W). At low discharge powers, amorphous structures were produced during the initial sputtering period. High (2 0 0)-axis orientation structures were formed when sputtering time was increased. The upper part of the coatings was composed of open columnar structures with extended voids along the column boundaries. Increasing the discharge power decreased the thickness of the amorphous layer. Consequently, the microstructures became dense and compact; however, the grain size did not change significantly. Meanwhile, an enhanced compressive stress was observed, followed by an increase in the texture coefficients of the (1 1 1) plane and lattice parameters. The physical properties of the coatings were improved by increasing the discharge power. The coating hardness was increased to approximately 32.1 GPa. In addition, the electrical resistivity was decreased to approximately 134 μΩ cm, and the light reflectivity in the infrared region (700–2400 nm) was increased to 75%. [ABSTRACT FROM AUTHOR]

Si-doped (AlCrMoTaTi)N coatings were deposited onto an Si substrate by radio-frequency magnetron sputtering of an AlCrMoTaTi alloy target under direct current bias in an N 2 /Ar atmosphere. The crystal, microstructural, mechanical, and electrical properties at different Si-target powers were investigated. As the Si content reached 7.51 at.%, the simple NaCl-type face-centered cubic structure of nitride was retained. Significant lattice decline and grain growth were observed in the nitride coatings. The microstructure of coatings transformed from loose columns with rough-faceted surface into dense ones with smooth-domed surface. The solubility of approximately 7.51 at.% Si content was demonstrated. Si incorporation significantly improved the mechanical properties of the coatings, but degraded their electrical properties. The hardness of the coatings increased from 20.7 GPa to 35.5 GPa, and the electrical resistivity increased from 793 μΩ cm to 3872 μΩ cm. [ABSTRACT FROM AUTHOR]

(TiVCrZrY)N coatings were deposited onto Si substrate by the radio-frequency (RF) magnetron sputtering of a TiVCrZrY alloy target in an N/Ar atmosphere. The crystal, microstructural, mechanical, and electrical properties at different N-to-total (N+Ar) flow-rate ratio ( R) values were investigated. The coating produced in pure Ar had an equiaxed structure with a hexagonal-close-packed phase. With increased R, the crystallinity and grain size markedly decreased. The microstructure of (TiVCrZrY)N coatings transformed from V-shaped columnar with a rough-domed surface into fine fibrous with a smooth surface. The amorphous transition layer above the substrate was also significantly thickened. The hardness of (TiVCrZrY)N decreased from 20.9 GPa to 18.9 GPa, and the electrical resistivity increased from 398.2 μΩ⋅cm to 21870 μΩ⋅cm. [ABSTRACT FROM AUTHOR]

Highlights: [•] Electrolytic deposition was used to fabricate Sn-coated MCMB electrodes. [•] The deposition current and the solution concentration affect the structure of the Sn-coated MCMB. [•] The Sn-coated MCMB has a large specific surface area. [•] The Sn-coated MCMB exhibits increased reversible capacity without sacrificing its cycling behavior. [ABSTRACT FROM AUTHOR]

Highlights: [•] The R N influences the structure and properties of (AlCrMoTaTi)N coatings. [•] The alloy coating has a composite structure with amorphous and bcc crystal phases. [•] The nitride coating displays V-shaped columnar structure with fcc crystal phase. [•] Increasing R N to 30% caused the hardness to reach maximum values of 30.6GPa. [•] Electrical resistivity increased to 8212μΩcm when R N increased to 50%. [ABSTRACT FROM AUTHOR]

(TiVCrZrHf)N coatings were deposited on Si substrates by reactive magnetron sputtering system. Their oxidation behaviors and structure were studied after static oxidation tests in air at different temperatures. The evolution of the chemical composition, microstructure, nanohardness, and electrical resistivity of these coatings after annealing at different temperatures in air was systematically analyzed. The as-deposited coating showed continued variation in structure from amorphous to columnar with the face-centered cubic crystal phase, but had no significant change in structure with increased annealing temperature to 300°C. The hardness of the coating was stable at a high value of 31.24GPa up to an annealing temperature of 300°C. However, a thin oxide overlayer was observed at 400°C, which increased in thickness at 500°C and thus drastically decreasing the hardness to 11.85GPa. Above 600°C, the coating was almost fully oxidized and became quite porous and loose. Accordingly, a very low hardness of only 2.3GPa was obtained. The electrical resistivity of the coatings followed the same trend as the hardness. The electrical resistivity of the as-deposited coating was about 144μΩ-cm, followed by an apparent increase to 100Ω-cm due to the formation of oxide phases. [ABSTRACT FROM AUTHOR]

Abstract: Ti–V–Cr–Al–N films were prepared by dc magnetron co-sputtering by utilizing TiVCr and Al targets. By using glancing incidence X-ray diffraction, a single NaCl solid solution phase with (200) preferred orientation for the Al-doped films was revealed, as opposed to the undoped films that possessed predominantly (111) preferred orientation. This indicates that Al addition can lead to the enhancement of adatom mobility and consequently, to a thermodynamically favorable (200) orientation. This also leads to grain growth and increased surface roughness. However, based on results from transmission electron microscopy, the microstructure morphology seemed independent of the Al concentration, implying that adatom mobility is not sufficient for the barriers present at the grain boundaries. Accordingly, hardness was enhanced by the increase in Al concentration. [Copyright &y& Elsevier]

Three heterometallic coordination polymers based on 4-amino-1,2,4-triazole (atrz), Cd2.98Fe2.02(atrz)6(SCN)10·2H2O (1), Cd2.86Co2.14(atrz)6(SCN)10·2H2O (2), and Cd2.02Ni2.98(atrz)6(SCN)10·2H2O (3), were synthesized. Crystal structures of the polymers were determined by single-crystal X-ray diffraction, X-ray powder diffraction, and infrared analysis. The complexes exhibit a 3-D structure and are isostructural, but entail different durations for transformation from a 1-D polymer to a 3-D structure. The results of vibrating sample magnetometry for1indicate that the complex exhibits weak paramagnetism. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we investigated the microstructure of (TiVCrZrHf)N multi-element coating deposited on Si(100) substrate by magnetron sputtering system. Interestingly, the film showed an unusual structure evolution. A continuous and amorphous initial (TiVCrZrHf)N layer formed on the substrate. As film thickness increased, randomly oriented small (TiVCrZrHf)N grains formed, followed by the development of columnar grains with FCC crystal phase. In contrast to previous studies, the nitride coatings grew on substrates with a 270-nm amorphous interlayer. Under appropriate parameters, the occurrence of the unusual microstructure could be attributed to the sluggish diffusion of the multi-principal components. The maximum hardness of 33.5GPa was obtained when coating was deposited under substrate bias of −100V and at substrate temperatures of 723K. [Copyright &y& Elsevier]

Abstract: In this study, TiVCr alloy coatings were deposited on Si substrates by magnetron sputtering system at different working pressures (0.33–1Pa). The TiVCr coatings have a composite structure with amorphous and body-centered cubic (bcc) crystal phases comprised of bundles of fine fibrous structures and V-shaped columnar structures, respectively. Compared with the amorphous zone, the crystalline zone has a denser and more compact structure. The coating microstructure became more porous as working pressure increased. Consequently, the crystal zones of the deposited coatings at 0.33Pa obtained higher hardness (11.6GPa) while the deposited coatings at 1Pa achieved lower hardness (4.5GPa). [ABSTRACT FROM AUTHOR]

Abstract: The (TiVCr)N coatings were deposited on Si substrate via rf magnetron sputtering of a TiVCr alloy target under dc bias in a N2/Ar atmosphere. The deposition rate of the coatings gradually decreased with increasing N2-to-total (N2 +Ar) flow ratio, R N. The TiVCr alloy and its nitride coatings exhibited a body-centered cubic (BCC) and a face-centered cubic (FCC) crystal structure, respectively. The preferred orientation of the (TiVCr)N coatings changed from (111) to (200) with increasing R N. In addition, the microstructure of the nitride coatings was also converted from a columnar structure with void boundaries and rough-faceted surface to a very dense structure with a smooth-domed surface. The grain size of the (TiVCr)N coatings decreased as the R N was increased. Accordingly, the hardness of the (TiVCr)N coatings was enhanced from 4.06 to 18.74GPa as the R N was increased. [ABSTRACT FROM AUTHOR]

Abstract: This study reports the influence of growth conditions on the characteristics of (TiVCrZrY)N coatings prepared by reactive magnetron sputtering at various N2-to-total (N2 +Ar) flow ratio, which is RN. The crystal structures, microstructure, and mechanical properties for different RN were characterized by electron spectroscopy for chemical analysis, X-ray diffraction, atomic force microscopy, field-emission-scanning electron microscopy, transmission electron microscopy, and nanoindentation. The results indicate that the TiVCrZrY alloy and nitride coatings have hexagonal close-packed (hcp)-type and sodium chloride (NaCl)-type solid–solution structures, respectively. The voids in the coatings are eliminated and the growth of the columnar crystal structures is inhibited along with an increasing RN. As a consequence, highly packed equiaxed amorphous structures with smooth surfaces are formed. The coatings accordingly achieved a pronounce hardness of 17.5GPa when RN =100%. [ABSTRACT FROM AUTHOR]

Presented are the solvothermal syntheses, structures, characterizations, and luminescent properties of four novel organic-modified cadmium chloride complexes constructed from CdCl 2 and imidazole (or its derivatives), namely [CdCl 2 (Im) 4 ] ( 1 , Im = imidazole), [CdCl 4 (HAPI) 2 ] ( 2 , API = N-(3-Aminopropyl)-imidazole), [Cd( μ -Cl) 2 (1-Mim) 2 ] ∞ ( 3 , 1-Mim = 1-methyl imidazole) and [CdCl 3 (HAPI)] ∞ ( 4 ). 1 and 2 feature a zero dimensional (0D) mononuclear structure with different mole ratios of Cd: Cl: ligand, while compound 3 and 4 bear infinite chains constructed from different subunits and connection modes. Worthy of note is that 4 represents a new structural type in the family of organic modified cadmium halides. The fluorescence spectra showed that compounds 1–4 exhibited emission peaks around 450 nm with the quantum yields of 23.01%, 5.84%, 27.31%, 5.71%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The present paper reports the influence of growth conditions on the characteristics of (TiVCrZrHf)N films prepared by rf reactive magnetron sputtering at various substrate temperatures. The nitrogen content is observed to decrease with increasing substrate temperature. The X-ray diffraction results indicate that all (TiVCrZrHf)N films are simple face centered cubic (FCC) structures. Initially, there is an obvious decrease followed by an increase in grain size with the increase in substrate temperature. The lower part of the microstructure has an amorphous structure. A nano grain structure (size ∼1nm) with a random orientation is also observed above the amorphous structure. The fully dense columnar structure with an fcc crystal phase then starts to develop. Extreme hardness of around 48GPa is obtained in the present alloy design. [Copyright &y& Elsevier]

Metal oxide nanomaterials have been widely applied in the high-performance gas sensors. For metal oxide semiconductors, high surface-to-volume ratio and the exposed crystal facets are the two key factors for determining their gas sensing performances. In order to study the effect of surface structure on the gas sensing properties, in this work, two types of copper oxide (CuO) nanostructures, CuO nanotubes (CuO NTs) with exposed surface plane of (111) and CuO nanocubes (CuO NCs) with exposed surface plane of (110), were obtained from Cu nanowires (Cu NWs) and Cu 2 O nanocubes (Cu 2 O NCs), respectively. The morphologies, crystal and surface structures were characterized by high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The gas-sensing performances of CuO NTs and CuO NCs for CO gas detection were then studied. The results demonstrated that compared to CuO NCs, the CuO NTs exhibited lower optimum working temperature and higher sensitivity for CO gas detection. At the operating temperature of 175 °C, the prepared CuO NTs exhibited high sensitivity, good selectivity, fast response and recovery times to CO gas. The present study indicates that for the same semiconductor sensing material, the surface crystal structure has significant influence on the sensing performance. [ABSTRACT FROM AUTHOR]

Reported here are the syntheses,structures, and characterizationsof four novel In–Sb–S compounds containing organic amines,namely, [PAH]3[In3Sb2S9] (PA = n-propylamine) (1), [Fe(en)3][In2Sb2S7] (en = ethylenediamine)(2), [Mg(dien)2][In2Sb2S7]·0.5H2O (dien = diethylenetriamine)(3), and In2(N,N-dmen)2Sb2S6(N,N-dmen = N,N-dimethylethylenediamine)(4). Compound 1features a [In3Sb2S9]n3n–layer assembled by the alternating linkageof the {In2Sb2S8}nribbons and the {In4Sb2S12}ndouble-ribbons. Both compounds 2and 3possess layered anionic parts with thesame stoichiometry of [In2Sb2S7]n2n–butdistinct linkage modes between the subunits of {In2S7} groups and Sb3+ions. Notably, the {In2Sb2S9} heterometallic cluster observed in 3is initially regarded as the secondary building unit (SBU)for the construction of the [In2Sb2S7]n2n–layer. Compound 4features a novel discrete inorganic–organichybrid molecule of In2(N,N-dmen)2Sb2S6. Through the structuralanalyses on 1–4, the organic aminesapplied played three different roles on the formation of the finalcrystalline products. For 1, the protonated n-propylamines arrange in the space around the anionic network andbalance the negative charge. For 2and 3, the chelating polyamines coordinate to central metal ions to formmetal complexes, which then act as space-filling and charge-balancingagents. For 4, two N,N-dimethylethylenediamines chelate to two In3+ions ofthe inorganic segment through coordination bonds, leading to the formationof a rare inorganic–organic hybrid cluster. At last, we gavea systematic discussion about the characteristics and roles of organicamines in all related In–Sb–S compounds. In one word,the work presented here enriches the structural chemistry of the main-groupheterometallic chalcogenidometalates, providing more chances for researchersto work out the rules in their composition– or structure–functionrelationship. [ABSTRACT FROM AUTHOR]

The crystal structures of the new compounds (IV) and (V) are determined by single crystal XRD. [ABSTRACT FROM AUTHOR]