Synthesis, characterization, and photoactivity of Ta2O5-grafted SiO2 nanoparticles.

Herein, we discuss the synthesis as well as material and photochemical characterization of nanometer-sized Ta(2)O(5) decorated, in a controlled fashion, on top of 20 nm diameter SiO(2) particles to yield a composite oxide with a tunable band-gap width. Particular emphasis is paid to control of particle size, and control of the distribution of the overlying oxide. The nanoscale dimension imparts a high surface area and introduces quantum confinement effects that displace the conduction band more negatively and the valence band more positively on the electrochemical scale of potentials.

Experimental technique using FTIR to estimate IR optical properties at variable temperatures: application to PMDA-ODA polyimide thin films from 100 to 380 degrees C.

An experimental technique is presented to measure reflectance at high sample temperature with respect to room temperature in the infrared using Fourier transform infrared fitted with a reflectometer. Sample temperature artifacts are accounted for by sequential measurements taken with the lamp source on and with the lamp source off. The sequential measurements are shown mathematically to correct for the modulation of sample and detector thermal emissions.