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To design and make new metal-organic frameworks with desired structure and consequently spatial properties, there need to choose both metal ion as a node and ligands as their linkers. In pillared metal-organic frameworks, the presence of two linkers make bifunctional MOFs. Here, a pillar two-dimensional metal-organic framework (MOF) with molecular formula [Zn(cba)(bpdb)].DMF (2DTMU-1) was obtained by the reaction of zinc(II) nitrate with 4,4'-methylenedibenzoic acid (H2cba) as the carboxylate linker and 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene (bpdb) as the N-donor pillar. The structure was determined by single-crystal X-ray diffraction and Fourier-transform infrared spectroscopy (FT-IR). 2DTMU-1 is based on a binuclear paddlewheel Zn(II) unit complexed by four bridging bidentate (dicarboxylate) V-shaped ligand, 4,4'-methylenedibenzoic acid (H2cba), this tetragonal array being connected by bpdb with a bridging azine group in the middle as a potential Lewis basic site, making two-dimensional metal-organic framework structure and shows a pore size of 18 × 12 Å2.

A simple and highly efficient one-pot method for the construction of α-hydroxyketone phosphates from terminal alkynes and H-phosphine oxides has been developed in the presence of PhI(OAc)2 and H2O. The present protocol provides an attractive approach to α-hydroxyketone phosphates in good to high yields, with the advantages of operation simplicity, the use of commercially available materials, broad substrate scope, high atom efficiency and good tolerance to scale-up synthesis.

A simple and facile copper-catalyzed synthesis of β-ketophosphine oxides via direct oxyphosphorylation of alkynes with H-phosphine oxides and dioxygen has been developed under mild conditions without any base or cocatalyst. A radical reaction pathway for the formation of β-ketophosphine oxides is proposed. An 18O labeling experiment suggested that the carbonyl oxygen atom of β-ketophosphine oxides originated from dioxygen.

A simple and catalyst-free method has been developed for the construction of β-hydroxyphosphine oxides through direct difunctionalization of alkenes with H-phosphine oxides and dioxygen under mild conditions. Preliminary mechanistic studies indicated that the hydroxyl oxygen atom of β-hydroxyphosphine oxide originated from the dioxygen and the present reaction might involve a radical process.

The structural and electronic properties of Nb2AlC have been studied using the ab initio pseudopotential approach based on density functional theory. The internal coordinates of Nb atom is determined to be (1/3, 2/3, 0.089). The equilibrium lattice parameters are computed to be a = 3.119 A and c = 13.92 A, in good agreement with experimental results. The band structure and density of states reveal that Nb2AlC is an electronic conductor. Both Nb 4d and Al 3p contribute to the electronic properties. Partial density of state indicates that a strong hybridization of Nb 4d and C 2p states. The charge density distribution shows that the Nb and C atoms form a strong Nb C Nb covalently bonded chain.

The evolutions of electronic structure and optical properties of SnO2 under hydrostatic pressure are studied theoretically using first-principle calculations. The calculation results show that the energy band gap of SnO2 expands with increasing pressure, and the relationship between them can be fitted well by a second order polynomial expression. The complex dielectric functions are calculated and it is found that its imaginary part moves to higher photon energy levels with increasing pressure; meanwhile the static dielectric function constant decreases correspondingly. The dependences of other optical properties, such as the reflectivity spectra and loss function, on the hydrostatic pressure are also calculated and obtained, and the relationships between the optical properties and hydrostatic pressure are discussed and analyzed.

A simple and facile copper-catalyzed synthesis of β-ketophosphine oxides via direct oxyphosphorylation of alkynes with H-phosphine oxides and dioxygen has been developed under mild conditions without any base or cocatalyst. A radical reaction pathway for the formation of β-ketophosphine oxides is proposed. An 18O labeling experiment suggested that the carbonyl oxygen atom of β-ketophosphine oxides originated from dioxygen.

A simple and catalyst-free method has been developed for the construction of β-hydroxyphosphine oxides through direct difunctionalization of alkenes with H-phosphine oxides and dioxygen under mild conditions. Preliminary mechanistic studies indicated that the hydroxyl oxygen atom of β-hydroxyphosphine oxide originated from the dioxygen and the present reaction might involve a radical process.

Considering the electric field of incident light along four particular directions [100], [110], [011], and [010], the optical properties of monoclinic MnWO4 were investigated by the first-principle methods. The calculated electronic structures show that the O 2p states and Mn 3d states dominate the top of the valence bands, while the W 5d and Mn 3d states play a key role in the bottom of the conduction bands. The dielectric function and other optical properties, including absorption coefficient, reflectivity spectra, and energy-loss spectra, were calculated and analyzed. The results predicted the maximum static dielectric function when the electric field of incident light was along the [100] direction; meanwhile the absorption edge was calculated to be consistent with the energy band gap and the values and positions of peaks in absorption coefficient are related with the electric field of light. Otherwise, it is found that the appearance of peaks in the energy-loss spectra is also dependent on the electric field and simultaneously corresponds to the edge of absorption spectra and the peaks' position of reflectivity spectra.

The effect of hydrostatic pressure on the crystal structure, electronic and optical properties of distorted rare-earth manganite TbMnO3 has been studied on the basis of first-principle calculations. The results reveal that the band gaps reduce quadratically with increasing pressure. The optical properties of TbMnO3 predict that the peaks in the dielectric function shift to higher photon energy due to the transformation of inner electronic states with increasing pressure. Otherwise, the peaks in the reflectivity spectra and loss function were also found to move to higher photon energy with pressure increasing and the relationships between the positions of these peaks and pressure can be fitted by third order polynomial expressions.

Al and Sb codoped ZnO thin films were prepared through a sol-gel spin coating method on glass substrates and annealed in different atmospheres. The XRD results show that the films have hexagonal wurtzite ZnO structure and SEM results reveal that the films annealed in hydrogen consist of hexagonal nanorods with diameters of 84 nm and lengths of 422 nm, however the films annealed in other atmospheres without nanorods. The photoluminescence (PL) spectrum shows that the emission peaks of the films are mostly at 390 and 460 nm, and the film annealed in hydrogen has the strongest intensity of peak at 390 nm and the film annealed in air has the strongest intensity of peak at 460 nm. The electrical properties show that the films annealed in hydrogen have a lowest resistivity of 1.02×10-3 Ω•cm.

Al and Sb codoped ZnO nanorod ordered array thin films have been deposited on glass substrate with a ZnO seed layer by hydrothermal method at different growth time. The effect of growth time on structure, Raman shift, and photoluminescence (PL) was studied. The thin films at growth time of 5 h consist of nanorods growth vertically oriented with ZnO seed layer, and the nanorods with an average diameter of 27.8 nm and a length of 1.02 μm consist of single crystalline wurtzite ZnO crystal and grow along [0 0 1] direction. Raman scattering analysis demonstrates that the thin films at the growth time of 5 h have great Raman shift of 15 cm −1 to lower wavenumber and have low asymmetrical factor Г a / Г b of 1.17. Room temperature photoluminescence reveals that there is more donor-related PL in films with growth time of 5 h.

ZnO thin films doped with Al concentrations of 1.0, 2.0, 3.0, 4.0, 5.0 at% were prepared by a sol–gel spin-coating method on glass substrates and respectively annealed at 550 °C for 2 h in hydrogen and air. The X-ray diffraction and selected-area electron diffraction results confirm that the Al doped ZnO thin films are of wurtzite hexagonal ZnO. The scanning electron microscope results indicate that the Al doped ZnO nanorod thin films can be got by annealing in hydrogen rather than in air. The optical properties reveal that the Al doped ZnO thin films have obviously enhanced transmittance in the visible region. The electrical properties show that the resistivity of 1.0 at% Al doped ZnO thin films has been remarkably reduced from 0.73 Ω m by annealing in air to 3.2 × 10 −5 Ω m by annealing in hydrogen. It is originated that the Al doped ZnO nanorod thin films annealed in hydrogen increased in electron concentration and mobility due to the elimination of adsorbed oxygen species, and multicoordinated hydrogen.

The β-Mn 2 V 2 O 7 crystals with strip-like shape were successfully synthesized by molten salt method in different molten salt. The samples were investigated by XRD, SEM, TEM, HRTEM and SAED. The results show molten salt species, molten salt content and heating temperature have great effect on the crystal structure and morphology. The products were found to have a monoclinic structure and possess a uniform strip-like shape with different grain size. The XRD patterns and the SAED patterns of single strip indicate that the β-Mn 2 V 2 O 7 single strip have single crystalline character. HRTEM image further substantiate that the β-Mn 2 V 2 O 7 strip have anisotropy growth and crystalline integrality.

The ZnO thin films co-doped with Al and Sb have been successfully deposited by a sol–gel spin-coating method on glass substrates and annealed at different temperature for 2 h in air. The annealing effects of different temperature on the structure and biaxial stress were characterized by X-ray diffraction. The results revealed that the annealed ZnO thin films mainly consist of ZnO with wurtzite structure, and the biaxial stress is lower during annealed at 550 °C. The annealed films have high transmittance in the visible region and show sharp absorption edges in the UV region. The optical band gap Eg values are 2.95, 3.03, 3.18 and 3.15 eV, which corresponding to the films annealed at 450, 500, 550, 600 °C, respectively. The resistivity of thin films reaches a minimum when the annealing temperature at 550 °C. The conducting mechanism is contributed to Sb substitute for Zn inducing two corresponding Zn vacancies.

The SiOC foam ceramics were prepared using polyurethane sponge and polysiloxane as raw materials. The effects of the pyrolysis temperature, the concentration of polysiloxane solutions, and the content of SiC nano-powder on compression strength of the SiOC foam ceramics have been investigated respectively. The optimum compression strength of SiOC foam ceramics is obtained at the pyrolysis temperature of 1250°C and the concentration of solution PSO of 0.8 g/ml. Adding SiC nano-powder into PSO can effectively increase compression strength of samples, and the maximum compression strength, 20.8 MPa, is obtained when the content of SiC nano-powder is 5 wt%. Microstructural study reveals that the foam ceramics have an open, uniform and interconnected porous structure with high porosity of 80%.

The electronic structures and optical properties of Tb1−xYbxMnO3 as a function of Yb element content x are investigated by employing the first-principles method. The calculation results indicate that the electronic states associated with the Yb element are dominated gradually and the inner electronic states move to the lower energy level with the increasing x. The dielectric function and other optical properties of Tb1−xYbxMnO3 such as the reflectance spectra are obtained and the results indicate that the static dielectric function reaches a maximum at about x = 0.75, while the fitting expression predicts a maximum when x = 0.69. In addition, it is found that one peak appearing at about 3.60eV in the reflectance spectra of TbMnO3 is driven to shift linearly towards higher energy level with the increasing x. However, another peak at about 29.63eV moves nonlinearly in the same situation.