Tianyou Peng

Combustion synthesis and photoluminescence of SrAl2O4:Eu,Dy phosphor nanoparticles

Abstract Eu2+,Dy3+ co-doped strontium aluminate (SrAl2O4) phosphor nanoparticles with high brightness and long afterglow were prepared by glycine–nitrate solution combustion synthesis at 500 °C, followed by heating the resultant combustion ash at 1100 °C in a weak reductive atmosphere of active carbon. The average particle size of the SrAl2O4:Eu,Dy phosphor nanoparticles ranges from 15 to 45 nm as indicated by transmission electron microscopy (TEM). The broad-band UV-excited luminescence of the SrAl2O4:Eu,Dy phosphor nanoparticles was observed at λmax=513 nm due to transitions from the 4f65d1 to the 4f7 configuration of the Eu2+ ion. The results indicated that the main peaks in the emission and excitation spectrum of phosphor nanoparticles shifted to the short wavelength compared with the phosphor obtained by the solid-state reaction synthesis method. The decay speed of the afterglow for phosphor nanoparticles was faster than that obtained by the solid-state reaction method.

Electrothermal volatilization of aluminum as 1-phenyl-3-methyl-4-benzoylpyrazolone[5] chelate for gaseous sample introduction in ICP-AES.

Based on gaseous compound introduction as 1-phenyl-3-methyl-4-benzoylpyrazolone[5](PMBP) chelate of aluminum by electrothermal vaporization in ICP-AES, a method for determination of trace aluminum was developed. Trace aluminum was vaporized at temperature of 1000 degrees C, and the vaporization behavior of aluminum chelate was detailedly investigated. Under the optimum conditions, the detection limit of aluminum was 0.6 ng ml(-1), and the relative standard deviation for 0.1 mug ml(-1) aluminum was 4.7% (n=8). The proposed method was applied to the determination of trace aluminum in rice flour reference materials, and the results well agreed with the reference values.

Nonlinear absorption and optical limiting properties in sol-gel solidified gold nanorods

The Optical nonlinearities and optical limiting (OL) properties of Sol-gel solidified gold nanorods were investigated by using Z-scan technique and OL measurement, respectively, with nanosecond pulses at 532nm. The experimental results show that their strong nonlinear optical performances depend on the sizes of nanorods. The surface plasmon absorption is the main mechanism.