Liu Yingliang

Luminescence Properties of Sr2SnO4:Sm3+ Afterglow Phosphor

A new long-lasting phosphorescence (LLP) phosphor, Sr2SnO4:Sm3+, which emits reddish-orange LLP upon UV-excitation, is prepared by a conventional high-temperature solid-state method. After irradiation under 247-nm UV light, Sr2SnO4:Sm3+ emits an intense reddish-orange emission afterglow from the 4G5/2 to 6HJ (J = 5/2, 7/2, 9/2) transitions. The afterglow decay curve of the Sm3+ -doped Sr2SnO4 phosphor contains a fast decay component and another slow decay one. Due to the presence of the slow decay component, the afterglow can be seen with the naked eye in the dark clearly for more than 1 h after removal of the excitation source.

Preparation, Characterization and Photocatalytic Activity of Pt-SiO2/TiO2 with Core-Shell Structure

Abstract SiO 2 /TiO 2 photocatalyst with core-shell structure were synthesized by sol-gel method, using SiO 2 microsphere with a mean size of about 300 nm as template. And then Pt was deposited on SiO 2 /TiO 2 by chemical reduction method. The obtained samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), diffuse reflectance spectra (DRS), X-ray photoelectron spectroscopy (XPS), and photoluminescence spectra (PL). The results show that Pt particles mainly in form of Pt(0) can be deposited on SiO 2 /TiO 2 surface un-uniformly. The absorption in visible light region and the separation efficiency of electron-hole pairs are enhanced obviously via Pt-deposition. The adsorption and kinetic constants of Rhodamine B (RB) over the obtained samples were evaluated. The results indicate that core-shell structure is helpful to improve the adsorption property. The presence of Pt on SiO 2 /TiO 2 surface is found to significantly enhance the photodegradation of RB, and the optimal deposition of Pt is 0.5 wt%.

Steady State and Time-Resolved Fluorescence Dynamics of Triphenylamine Based Oligomers with Phenylene/Thiophene/Furan in Solvents

We investigate the photo-physical properties of a series of triphenylamine-based oligomers by steady-state and picosecond transient fluorescence measurements in solvents. The oligomers are composed alternatively with triphenylamine and phenylene/thiophene/furan group, bridged by vinyl group (PNB/PNT/PNF). Their fluorescence spectra show bathochromic phenomenon with solvent polarity and viscosity increasing. The fluorescence decays are bi-exponential for PNB and PNT, and tri-exponential for PNF in THF and aniline. The strong viscosity dependence suggests conformational relaxation along the PNF chain after photo excitation.

Synthesis of rod-like ternary carbide LaNiC2 by a solvothermal route

LaNiC2 was synthesized by a solvothermal route in a stainless steel autoclave at 600 °C. In this process, nickel chloride, lanthanum chloride and toluene were used as raw materials, and metallic Na and Li alloy were used as reductant. The products were characterized with an X-ray diffractometer (XRD) and a scanning electron microscope (SEM). The LaNiC2 products consisted of a great deal of micro-rods. The micro-rods had diameters ranging from hundreds of nanometers to several micrometers and lengths ranging from several micrometers to tens of micrometers.