Multilayer Nano Ti∕TiO[sub 2]–Pt Electrode for Coal-Hydrogen Production

Multilayer nanoporous Ti/TiO{sub 2} films were obtained by controlling electro-oxidation potentials in a sulfuric acid solution. After etching in a dilute hydrogen fluoride solution, the porous layers were deposited and intercalated with Pt and Pt-Ru to form Ti/TiO{sub 2}-Pt and Ti/TiO{sub 2}-PtRu electrodes by using the cyclic voltammetric method. An electron diffraction spectroscopy was used to examine the electrode surface structure. The catalytic activity of the electrodes for electro-oxidation of coal shows that the multilayer nanoporous Ti/TiO{sub 2}-Pt structure improves the electrode performance in comparison to a pure Pt electrode and a Pt coated Ti electrode. The Ti/TiO{sub 2}-Pt-Ru (1: 2) electrode shows even better catalytic activity than the Ti/TiO{sub 2}-Pt. Anode gas analysis shows that the coal electro-oxidation produces mainly CO{sub 2} with trace amount of CO and the cathode gas is pure hydrogen. We also observed some lower hydrocarbon by-products, such as methane. The amount of CO{sub 2} is only about 10% of the amount of H{sub 2} produced.