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The electronic structure of the layered ternary carbides Ti2SnC and Ti2GeC has been investigated by means of ab initio linear combination of atomic orbital calculations. The calculated band structure shows that the electrical conductivity for both Ti2SnC and Ti2GeC is metallic and anisotropic with a high density of states at the Fermi level. The electrical conductivity of Ti2SnC is, however, higher than that of Ti2GeC. The major factors governing the electronic properties are {pd} hybridization from Ti 3d and C 2p states. Compared to the structure of TiC, the presence of Sn or Ge changes the Ti-C-Ti-C covalent bond chain into a Ti-C-Ti-Sn or Ti-C-Ti-Ge bond chain through its reaction with Ti, forming the layered structure.

In this work, LaPO4:Ce, Tb phosphors were prepared by firing a LaPO4:Ce, Tb precipitate using an ionic-liquid-driven supported liquid membrane system. The entire system consisted of three parts: a mixed rare earth ion supply phase, a phosphate supply phase, and an ionic-liquid-driven supporting liquid membrane phase. This method showed the advantages of a high flux, high efficiency, and more controllable reaction process. The release rate of PO43− from the liquid film under different types of ionic liquid, the ratio of the rare earth ions in the precursor mixture, and the structure, morphology, and photoluminescence properties of LaPO4:Ce, Tb were investigated by inductively coupled plasma-atomic emission spectroscopy, X-ray diffraction, Raman spectra, scanning electron microscopy, and photoluminescence emission spectra methods. The results showed that a pure phase of lanthanum orthophosphate with a monoclinic structure can be formed. Due to differences in the anions in the rare earth supply phase, the prepared phosphors showed micro-spherical (when using rare earth sulfate as the raw material) and nanoscale stone-shape (when using rare earth nitrate as the raw material) morphologies. Moreover, the phosphors prepared by this method had good luminescent properties, reaching a maximum emission intensity under 277 nm excitation with a predominant green emission at 543 nm which corresponded to the 5D4-7F5 transition of Tb3+.

Carbon nanotubes (CNTs) can be electronically conducting or semiconducting, and they are lightweight and have high stability. TiO 2 has been studied for applications in optics, microelectronics, and photocatalysis. Hybrid CNTs/TiO 2 shows unique photocatalytic and electrical properties for enhanced performances as solar cell electrode, sensors, and catalysts. This study is focused on shortening multiwalled CNTs (MWCNTs) and attaching TiO 2 nanoparticles onto MWCNTs by electrostatic attraction. A mechanical and chemical hybrid method is used to tailor CNT length. Opposite z-potentials are achieved for CNT and TiO 2 nanoparticle suspensions under the same pH. TiO 2 nanoparticles are attached onto CNTs for surface modification by electrostatic attraction.

TiO2 particles coated Multi-walled carbon nanotubes (MWCNT/TiO2 composite) were prepared via a sol-gel method using Multi-walled carbon nanotubes (MWCNT) and tetrabutyl titanate as raw materials. The phase constitutes and microstructures of the prepared composite were analyzed by XRD and TEM, respectively. Their photocatalytic activities were investigated under simulated ultra-violet light and visible-light irradiation for the degradation of methyl orange (MO) and methylene blue (MB) aqueous solution, respectively. The experimental results indicated that TiO2 calcined at temperatures of 400-600 degrees C in the MWCNT/TiO2 composite was mainly composed of nanometric anatase. The composite exhibited enhanced absorption properties in the visible-light region compared to pure TiO2, which was attributed to the enhanced light electron-hole separation by adding MWCNTs.