Papers by Author: Chun An Ma

Abstract: Pd electrocatalysts supported on TiO2 nanotubes (TNTs) were prepared and used for the oxidation of ethanol in alkaline media. The morphology and structure of the TNTs and the Pd-TNTs/Ti catalyst were characterized by field emission scanning electron microscopy (FESEM). The FESEM results showed that the nanotube structure could be obtained after Ti anodized for 40 min at 20 V under 25 °C, and the nanotube length increased with anodizing time. TNTs/Ti40, TNTs/Ti50 and TNTs/Ti90 templates were prepared with Ti anodized for 40 min, 50 min and 90 min respectively. The composite catalysts activities were measured by cyclic voltammetry (CV), impedance spectroscopy and chronoamperometry. The results indicated that the Pd-TNTs/Ti50 catalyst had higher catalytic activity for ethanol oxidation compared with Pd-TNTs/Ti40 and Pd-TNTs/Ti90 catalysts.

Abstract: A novel non-metal electrocatalyst based on platelet carbon nanofiber (p-CNF) is prepared, and a palladium electrocatalyst supported on activated carbon (AC) is also synthesized. The physico-chemistry properties of the p-CNF and palladium catalyst on AC (Pd/AC) are investigated by high resolution transmission electron microscopy, N2 physisorption and Raman spectra analysis. From cyclic voltammetric studies, it is found that p-CNF is more active than Pd/AC in acidic media. The p-CNF shows a more positive oxygen reduction reaction (ORR) onset reduction potential and a higher oxygen reduction current density than Pd/AC. Moreover, the ORR is controlled by a surface reaction process when Pd/AC is used, while it becomes diffusion controlled when p-CNF is used.