In this paper, three-dimensional ordered macroporous platinum catalysts with high real sur- face area were synthesized using the inverted col- loidal crystals template technique and have been employed for the electrooxidation of methanol. The morphology and electrocatalytic behavior of the po- rous Pt electrodes were investigated with atomic force microscopy and electrochemical techniques. For the same amount of Pt deposited, the real sur- face areas of the electrodes are 9.16 and 8.00 cm2 for the porous electrodes with pore size of 320 and 500 nm respectively, which are more than 5 times larger than the directly deposited Pt electrode (1.4 cm2). The pore size effect on the methanol elec- trooxidation was investigated by testing low concen- tration solution of methanol and porous materials with different pore sizes. The synthesized macroporous Pt electrode shows high stability toward the electrooxi- dation of methanol and is promising for the direct methanol fuel cell.
A composite material of nitric acid oxidized multiwalled carbon nanotube (MWNT) and Nation was prepared. Such composite was modified on a glassy carbon electrode to determine trace of lead by differential pulsed voltammetry. In pH=6.47 NaNO3 solution, Pb^2+ ions were accumulated on the modified electrode at -0.4 V. Compared with a bare and a Nation film coated electrode, the composite coated GC electrode can reduce the accumulating potential and eliminate the toxic character of mercury. The calibration plots were linear at low concentration of 5.0× 10^-9-2.0× 10^-8 mol/L and high concentration of 2.5× 10^-8-5.0× 10^-6 mol/L. The performances characteristics indicate that the electrode can be used to determine trace Pb^2+ ions.