Iodinated Charcoal as Electrocatalyst for Oxygen Reduction Reaction

Large quantity of iodinated charcoal (I-AC) is firstly prepared by simple ball-milling activated chargoalin the presence of iodine. The resultant I-AC contains iodine of 0.59 at.% (EDS) and shows that the morphology is changed from random powder into flake-like platelet. It is uased as electrocatalyst for oxygen reduction reaction (ORR), exhibiting outstanding electrocatalytic activities with higher selectivity, better tolerance to methanol crossover than those of the starting AC and commercial Pt/C electrocatalysts.

Measuring Bimodal Crystallographic Texture in Ferroelectric PbZrxTi1-x O3 Thin Films

A powder x-ray diffraction method has been developed to quantify textured volume fractions in thin films. It has been applied to {111}, {100} and randomly oriented PbZrxTi1-xO3 in 200 nm thick films used for ferroelectric random access memory applications. The integrated and peak intensities of 100, 110, 200 and 222 Bragg peaks from an untextured PZT film were determined by applying a thickness correction to a θ–2θ scan obtained from random powder of the same composition as the film. X-ray scans were made on the same peaks from the PZT film specimens. The distributions of grain orientation for the {111} and {100} populations in the films were determined from ω scans which were obtained from the films using 100, 200 and 222 scattering angles and corrected for defocussing and absorption. To determine the total volume fraction of each population of grains, the ratios of the integrated film peak intensities to the corrected powder integrated peak intensities were multiplied by the integrals of the corrected ω scans.