Reaction in photofuel cells using allophane–titania nanocomposite electrodes

Abstract

Allophane-titania nanocomposite electrodes for photofuel cells were prepared from titanium alkoxide sols dispersing the natural clay mineral allophane. The electrochemical measurements indicated that the oxidative degradation of starch in the solutions and suspensions enhanced the generation of electricity during UV irradiation. CO2 was observed as the degradation product. A higher photocurrent was observed using the allophane-titania nanocomposite electrode adsorbing a greater amount of the starch molecules. Allophane increased the capacity of the electrode to adsorb the starch molecules, even from the suspensions. This brought the molecules close to the titania nanoparticles, on which their oxidation induced the generation of electricity.

Visible‐Light‐Responsive TiO2/NiFe Mixed Metal Oxide‐Carbon Photocatalytic Fuel Cell with Synchronous Hydrogen Peroxide Production

“…When methanol, ethanol and glucose are used as fuels, the fuels are almost oxidized to CO 2 in a stoichiometric manner. [20,21] The PFC consists of a photoanode, a cathode and a reaction chamber with a certain proportion of fuel and electrolyte solution. TiO 2 , WO 3 , BiVO 4 , SnO 2 and Fe 2 O 3 were used as photoanode catalysts of PFC, [22][23][24][25][26][27][28][29][30][31] among which the TiO 2 was mostly employed.…”

ELECTROCHEMICAL AND PHOTO-ELECTROCHEMICAL PROCESSES OF METHYLENE BLUE OXIDATION BY Ti/TiO2 ELECTRODES MODIFIED WITH FE-ALLOPHANE

“…Recently, has been carried out a study with allophane-TiO 2 nanocomposite photocatalyst to degrade trichloroethylene (TCE) under UV irradiation. The catalytic efficiency was compared with the TiO 2 and the allophane-TiO 2 mixture [20]. TCE was transformed into intermediate products, on the TiO 2 , during the UV irradiation further this compound was rapidly absorbed on the allophane and gradually degraded after diffusing to the TiO 2 .…”

Photoelectrochemical properties of dye-dispersing allophane–titania composite electrodes

“…A method to increase the concentration is the use of the appropriate adsorbents. Actually, a higher short circuit current was observed in a photofuel cell using the 0.10% allophane-containing titania electrode than that with the normal titania electrode (Nishikiori et al, 2012b(Nishikiori et al, , 2014a. Allophane effectively adsorbed the glucose and starch molecules and then brought them close to the titania nanoparticles, on which their oxidation induced the electrogeneration.…”

“…400 nm as previously reported. The TEM image of the 1.0% allophane-titania composite powder was previously reported (Nishikiori et al, 2012b(Nishikiori et al, , 2014a. The allophane consisted of ca.…”