Triangular Au-Ag framework nanostructures （TFN） were synthesized via a multi-step galvanic replacement reaction （MGRR） of single-crystalline triangular silver nanoplates in a chlorauric acid （HAuCl4） solution at...Triangular Au-Ag framework nanostructures （TFN） were synthesized via a multi-step galvanic replacement reaction （MGRR） of single-crystalline triangular silver nanoplates in a chlorauric acid （HAuCl4） solution at room temperature. The morphological, compositional, and crystal structural changes involved with reaction steps were analyzed by using transmission electron microscopy（TEM）, energy-dispersive X-ray spectrometry （EDX）, and X-ray diffraction. TEM combined with EDX and selected area electron diffraction confirmed the replacement of Ag with Au. The in-plane dipolar surface plasmon resonance （SPR） absorption band of the Ag nanoplates locating initially at around 700 nm gradually redshifted to 1 100 nm via a multi-stage replacement manner after 7 stages. The adding amount of HAuCl4 per stage influenced the average redshift value per stage, thus enabled a fine tuning of the in-plane dipolar band. A proposed formation mechanism of the original Ag nanoplates developing pores while growing Au nanoparticles covering this underlying structure at more reaction steps was confirmed by exploiting surface-enhanced Raman scattering （SERS）.展开更多
A new metal-organic framework, {Zn[Zn3（BTA）3（μ3-OH）（H2O）3]2}n 1, has been synthesized under hydrothermal reaction of ZnCl2 and bis（5-tetrazolyl）amine （H2BTA）, and characterized by elemental analysis, FT-IR,...A new metal-organic framework, {Zn[Zn3（BTA）3（μ3-OH）（H2O）3]2}n 1, has been synthesized under hydrothermal reaction of ZnCl2 and bis（5-tetrazolyl）amine （H2BTA）, and characterized by elemental analysis, FT-IR, Raman spectrum, X-ray single-crystal diffraction, TGA and photoluminescence measurements. Compound 1 crystallizes in the trigonal system, space group P-3cl, a = 13.667（3）, c = 12.981（3） A, V = 2099.6（8） A3 and Z = 2. The BTA2- ligand in 1 assumes theμ3 tetradentate mode with both 1,2- and 1,4-tetrazole bridges, generating an unusual 2-D layer, in which the [Zn3（μ3-OH）] triangular motifs act as three-connecting nodes and the mononuclear Zn atoms as six-connecting nodes that are inter-linked by organic ligands. Adjacent 2-D metal-organic layers are linked by strong hydrogen bonds to form a novel 3-D supramolecular framework. Complex 1 exhibits blue fluorescence emission in the solid state at ambient temperature.展开更多
基金Project(10804101)supported by the National Natural Science Foundation of ChinaProject(2007CB815102)supported by the National Basic Research Program of ChinaProject(2007B08007)supported by the Science and Technology Development Foundation of Chinese Academy of Engineering Physics,China
文摘Triangular Au-Ag framework nanostructures （TFN） were synthesized via a multi-step galvanic replacement reaction （MGRR） of single-crystalline triangular silver nanoplates in a chlorauric acid （HAuCl4） solution at room temperature. The morphological, compositional, and crystal structural changes involved with reaction steps were analyzed by using transmission electron microscopy（TEM）, energy-dispersive X-ray spectrometry （EDX）, and X-ray diffraction. TEM combined with EDX and selected area electron diffraction confirmed the replacement of Ag with Au. The in-plane dipolar surface plasmon resonance （SPR） absorption band of the Ag nanoplates locating initially at around 700 nm gradually redshifted to 1 100 nm via a multi-stage replacement manner after 7 stages. The adding amount of HAuCl4 per stage influenced the average redshift value per stage, thus enabled a fine tuning of the in-plane dipolar band. A proposed formation mechanism of the original Ag nanoplates developing pores while growing Au nanoparticles covering this underlying structure at more reaction steps was confirmed by exploiting surface-enhanced Raman scattering （SERS）.
基金supported by the National Natural Science Foundation of China (Nos.50632030 and 10474077)
文摘A new metal-organic framework, {Zn[Zn3（BTA）3（μ3-OH）（H2O）3]2}n 1, has been synthesized under hydrothermal reaction of ZnCl2 and bis（5-tetrazolyl）amine （H2BTA）, and characterized by elemental analysis, FT-IR, Raman spectrum, X-ray single-crystal diffraction, TGA and photoluminescence measurements. Compound 1 crystallizes in the trigonal system, space group P-3cl, a = 13.667（3）, c = 12.981（3） A, V = 2099.6（8） A3 and Z = 2. The BTA2- ligand in 1 assumes theμ3 tetradentate mode with both 1,2- and 1,4-tetrazole bridges, generating an unusual 2-D layer, in which the [Zn3（μ3-OH）] triangular motifs act as three-connecting nodes and the mononuclear Zn atoms as six-connecting nodes that are inter-linked by organic ligands. Adjacent 2-D metal-organic layers are linked by strong hydrogen bonds to form a novel 3-D supramolecular framework. Complex 1 exhibits blue fluorescence emission in the solid state at ambient temperature.
