Photofuel cells using glucose-doped titania

Glucose-doped titania electrodes were prepared from titanium alkoxide sols containing glucose in order to examine the validity of the fuel material concentrated on the photocatalyst surface. The observed photocurrent and CO(2) and H(2)O productions indicated that the oxidation of the glucose enhanced the generation of electricity during the UV irradiation. Steam treatment of the electrodes improved the glucose oxidation and the photocurrent. However, refluxing of the precursor sol did not improve them. Not only the titania conductivity, but also the contact between the glucose and titania is important in order to obtain a high photofuel electric conversion. The concentration of the fuel material on the photocatalyst surface improved the energy conversion efficiency.ArticleAPPLIED CATALYSIS B-ENVIRONMENTAL. 106(1-2):250-254 (2011)journal articl

Photocatalytic degradation of chlorinated propenes using TiO2

The photocatalytic degradation of chlorinated propenes using TiO2 was investigated by FTIR spectroscopy. The chlorinated propenes were degraded to HCl, CO2, CO, H2O, and HCOOH during UV irradiation. During the degradation of 3-chloro-1-propene, the concentrations of CO2, CO, and HCOOH increased just after starting the irradiation. The onset of the HCl formation was delayed. On the other hand, the onset of the HCOOH formation was delayed during the degradation of 1-chloro-1-propene. During the degradation of 2-chloro-1-propene, the rate of the HCOOH production was slower than that during the degradation of 3-chloro-1-propene although the HCl production was not delayed. These results indicated that HCOOH was produced by the degradation of the double-bonded carbon bonding to two H atoms during the initial stage. The chlorinated compounds were preferentially produced from the double-bonded carbon bonding to the Cl atom and rapidly degraded to HCl, CO2, and CO during the initial stage. The residual part was degraded in the latter steps. Furthermore, it is suggested that the Cl atom on one of the double-bonded C atoms of the propenes was transferred to the other C atom before the degradation. Consequently, the double-bonded carbon bonding to two H atoms in 2-chloro-1-propene was chlorinated, then degraded to HCl, CO2, and CO during the initial stage.ArticleRESEARCH ON CHEMICAL INTERMEDIATES. 41(10):7641-7654 (2015)journal articl

Photo-electric conversion in dye-doped nanocrystalline titania films

Influences of the titania nanostructure and dye dispersion in a dye-doped titania electrode on its photoelectric conversion property were investigated by simple spectroscopic and electric measurements. The dye-doped nanocrystalline titania electrodes were prepared on the glass plates coated with ITO and normal crystalline titania films by the following two procedures: (1) the dye-doped titania gel films were prepared from a titanium alkoxide solution containing the dye and then steam-treated, and (2) the titanium alkoxide sol containing the dye was refluxed and then spread onto the plates. The photocurrent quantum efficiency remarkably increased by the steam treatment and the reflux compared to that of the untreated dye-doped electrode consisting of amorphous titania gel. The efficiency in the former was higher than that in the latter. The growth and crystallization of the titania particles and the decrease in the defect density by these treatments improved the electric conductivity. The steam treatment was the more prominent method because it enhanced the electric conductivity of the titania depending on its nanostructure and the dye-titania interaction depending on the dye dispersion. These factors appear to play important roles in transport in the electron through the electrode.ArticleJOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY. 207(2-3):204-208 (2009)journal articl

Influence of adding carbon nanotubes on photoelectric conversion properties of dye-doped titania gel

Multiwalled carbon nanotubes (MWCNTs) were incorporated into amorphous dye-doped titania gel by the sol-gel method at room temperature. The working electrodes were prepared by coating the ITO glass with the sol-gel titania precursor containing the dye and MWCNTs. The photoelectric conversion properties of the electrodes were examined by simple spectroscopic and electric measurements. The photocurrent spectrum originated from the absorption of the dye. The short circuit photocurrent was enhanced by adding a small amount of MWCNTs evenly to the amorphous dye-doped titania gel. The open circuit voltage was due to the semiconducting characteristics property of the titania gel. The experimental results indicated the electron transport from the dye excited states to the MWCNTs through the titania gel. The MWCNTs functioned as bridges between the titania and ITO. Steam treatment of the titania gel electrodes significantly increased the photoelectric performance due to crystallization of the titania and enhancement of the dye-titania interaction forming the chelate complex on the titania particle surface.ArticleRESEARCH ON CHEMICAL INTERMEDIATES. 38(8):1857-1869 (2012)journal articl

BROMI/TBC1D32 together with CCRK/CDK20 and FAM149B1/JBTS36 contributes to intraflagellar transport turnaround involving ICK/CILK1

Primary cilia are antenna-like organelles that contain specific proteins, and are crucial for tissue morphogenesis. Anterograde and retrograde trafficking of ciliary proteins are mediated by the intraflagellar transport (IFT) machinery. BROMI/TBC1D32 interacts with CCRK/CDK20, which phosphorylates and activates the ICK/CILK1 kinase, to regulate the change in direction of the IFT machinery at the ciliary tip. Mutations in BROMI, CCRK, and ICK in humans cause ciliopathies, and mice defective in these genes are also known to demonstrate ciliopathy phenotypes. We here show that BROMI interacts not only with CCRK but also with CFAP20, an evolutionarily conserved ciliary protein, and with FAM149B1/JBTS36, a protein in which mutations cause Joubert syndrome. In addition, we show that FAM149B1 interacts directly with CCRK as well as with BROMI. Ciliary defects observed in CCRK-knockout (KO), BROMI-KO, and FAM149B1-KO cells, including abnormally long cilia and accumulation of the IFT machinery and ICK at the ciliary tip, resembled one another, and BROMI mutants that are defective in binding to CCRK and CFAP20 were unable to rescue the ciliary defects of BROMI-KO cells. These data indicate that CCRK, BROMI, FAM149B1, and probably CFAP20, all together regulate the IFT turnaround process under the control of ICK

Photoinduced electron transport in dye-containing titania gel films

Amorphous dye-containing titania gel films were prepared on ITO electrodes coated with a crystalline titania foundation from titanium alkoxide sols containing a dye at room temperature. Photoinduced electron transport in the amorphous titania gel film was investigated by spectroscopic and photovoltaic measurements. Influences of the structure and morphology of the multilayered film on the photoelectron transport and electrically conductive properties were discussed. The photocurrent was observed from only the layer contacting the crystalline titania foundation. The electron transport from the amorphous upper layers was limited. Steam treatment of the electrodes improved the electron transport due to crystallization of the amorphous titania to anatase accompanied by enhancement of its electrical conductivity. The efficiency of the dye-sensitized electron transport in the steam-treated titania film was close to that of the anatase film prepared by heating at 773 K. The dye-containing titania layers functioned as efficient sensitizers.ArticleRSC ADVANCES. 2(10):4258-4267 (2012)journal articl