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51.
Electrochemical reduction of carbon dioxide into value-added products is a promising way to recycle the greenhouse gas, thus solving the crisis of global warming. Pressing challenges remain in regulating the catalytic selectivity. In this work, we demonstrated a metal-organic frameworks-assisted approach to synthesizing In species loaded on the surface of N doped carbon matrix. By controlling the particle sizes, the catalytic selectivity can be easily altered. The obtained Inc/NC possesses the outstanding capability for converting CO2 into CO. And 80.09% Faraday efficiency (FE) of CO can be achieved at 0.8 V vs. RHE. While the In2O3/C exhibits different catalytic behaviors, the main product is formic acid and the FE is more than 50% at 0.8 V vs. RHE. The selectivity reversal can be attributed to the strong interactions between In clusters and N atoms of carbon supports, which efficiently inhibits the formation of the by-product, formic acid. Our research has paved a new way to modulate catalytic selectivity by manipulating the fine structures of the catalysts. 相似文献
52.
Single crystals of SrIr9In18 were obtained by induction melting of the elements in a glassy carbon crucible followed by annealing at 1070 K. SrIr9In18 was structurally characterized by X-ray powder and single crystal diffraction: P4 m2, a = 811.21(5), c = 854.49(5) pm, wR2 = 0.0511, 1223 F2 values, and 46 variables. The structure is of a new type. The basic building units are Ir@In8 (distorted square-prismatic, square anti-prismatic and bicapped trigonal prismatic coordination) and Ir@In9 (distorted trigonal prismatic coordination) polyhedra, which condense to a three-dimensional network, which leaves large cavities for the strontium cations, which are coordinated to four iridium and twelve indium atoms. The [Ir9In18]2– polyanionic network is stabilized through Ir–In (267–290 pm) and In–In (302–354 pm) bonding. 相似文献
53.
The indium-rich intermetallic compound SrIrIn6 was synthesized from the elements in a sealed tantalum ampoule at 1173 K, followed by slow cooling for crystal growth. SrIrIn6 crystallizes with a new structure type which was characterized by X-ray powder and single crystal diffraction: Pmma, a = 852.34(2), b = 434.54(5), c = 1059.18(6) pm, wR2 = 0.0178, 884 F2 values, and 32 variables. The SrIrIn6 structure shows two basic building units: (i) Ir@In9 tricapped trigonal prisms (261–292 pm Ir–In) and (ii) distorted bcc In@In8 cubes (301 to 329 pm In–In). The strontium cations fill cages within the complex three-dimensional [IrIn6] network and have coordination number 13 (Sr@In13) in form of a tricapped pentagonal prism. The SrIrIn6 structure can be described as a simple intergrowth variant of SrIrIn4 (LaCoAl4 type) with indium slabs. The crystal chemical similarities with the structures of SrIrIn4, SrIr2In8 and Eu3Ir2In15 are discussed. 相似文献
54.
Organogallium and ‐indium compounds are useful reagents in organic synthesis because of their moderate stability, efficient reactivity and high chemoselectivity. Carbogallation and ‐indation of a carbon‐carbon multiple bond achieves the simultaneous formation of carbon‐carbon and carbon‐metal bonds. Heterogallation and ‐indation construct carbon‐heteroatom and carbon‐metal bonds. Therefore, these reaction systems represent a significant synthetic method for organogalliums and ‐indiums. Many chemists have attempted to apply various types of unsaturated compounds such as alkynes, alkenes, and allenes to these reaction systems. This minireview provides an overview of carboindation and ‐gallation as well as heteroindation and ‐gallation. 相似文献
55.
利用Raman光谱对结晶紫(Crystal Violet,CV)在纳米磷化镓(GaP)粉体表面的吸附状态进行了分析.结果表明:与普通拉曼散射谱(Normal Raman Scattering,NRS)相比,结晶紫表面增强拉曼散射(Surface Enhanced Raman Scattering,SERS)谱的4种振动模式,即:中央键的呼吸振动、环-C -环面外弯曲振动、环C-H面外弯曲振动以及N-环伸缩振动,在纳米GaP粉体表面得到增强;通过分析吸附前后结晶紫拉曼散射峰相对强度的变化,确定了结晶紫在纳米GaP粉体表面的吸附取向,并对其表面增强散射机理进行了探讨. 相似文献
56.
57.
《Current Applied Physics》2020,20(8):953-960
Thickness influence on structural, optical and electrical properties of sputtered indium tin oxide (ITO) with thickness ranging from 60 up to 430 nm films has been studied. At the increase of the film thickness crystallinity degree and grain size increased, whereas tensile structural distortion as well as resistivity decreased. It was observed that a microstructure evolution takes place: the initial amorphous layer evolved in polycrystalline phase, with a grain–subgrain surface morphology. Carrier concentration increased at the increase of the film thickness and a general relationship between electrical characteristics and structural distortion has been found. In thinner films larger tensile distortion allowed to include larger amount of interstitial O and/or Sn atoms in the lattice. An appreciable impact of the thickness was also observed on electro-optical properties in terms of changes in energy gap, resistivity and optical absorption. Silicon heterojunction solar cells have been produced and Jsc as high as 33.0 mA/cm2 has been obtained. 相似文献
58.
Duringthepastdecade,considerableattentionhasbeenfocusedontheorganoindiumchemistry.'AhandfulofpaPersontheaPplicationofallylindinmreagefltsandindinmpowdermediatedorganicreactionwerereported.'Mostrecelltly,indiumtfichloridehasbeenusedinorganicsynthesis.ForexamPle,InCl3-Me3SiClsystemhasbeenusedtopromotetheMukaiyamaaldolreaction,'Whiletheadditionofallylicstannanestoalde-hydespromotedbyInCl3hasalsobeenreported.'ItwasindicatedthatasanewLewisacidpromoter,InCl3mayreplacetheotherLewisacidssuchasB… 相似文献
59.
60.
In this study, the effect of ultraviolet treatment on the band bending at the poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate)/indium tin oxide (PEDOT:PSS/ITO) interfaces were researched. The authors suggested that ultraviolet treatment could lead to a reduction in the band bending at the PEDOT:PSS/ITO interface, owing to the removal of carbon contamination at the ITO surfaces and a decrease in the number of the trap-states at the PEDOT:PSS/ITO interface. 相似文献