Papers by Author: Kohsuke Mori

Abstract: The fluorine-modified mesoporous silica HMS(F20) was synthesized by using the mixture of TEFS(SiF(OC2H5)3) and TEOS(Si(OC2H5)4) as the silica source. The specific surface and pore size distribution were characterized by N2 adsorption and the hydrophilic-hydrophobic property was measured by water adsorption. The photocatalytic activities of TiO2 nanoparticles loaded on HMF(F20) and HMS were investigated for the degradation of iso-butanol diluted in water. The results show that the fluorine-modified mesoporous silica HMS(F20) has higher hydrophobic property than HMS and the TiO2/HMS(F20) exhibits the higher photocatalytic activity than TiO2/HMS. The hydrophobic mesopores benefit the condensation of hydrophobic organic compounds diluted in water, which results in higher photocatalytic degradation efficiency.

Abstract: For the synthesis of the nano-sized Ag metal particle, the sodium borohydride for the reducing agent was added into the aqueous solution of the AgNO3 with 3-mercapto-propionic acid as protective agent. Because the surface of nano-sized Ag metal particle was protected by the adsorbed 3-mercapto-propionic acid, the synthesis of the aqueous colloid system with high density became possible. The negative charge of carboxylate anion protect the aggregation of metal particles in the solution of high pH value (pH > 5), but the aggregation was occurred in the solution of low pH value (pH < 2). By changing the quantity of the agent of propionic acid and the pH value of solution, the particle size can be controlled optionally in the range of 50~200 nm.

Abstract: The synthesis of the hydrophobic mesoporous silica MS(F) was performed using tetraethyl orthosilicate, triethoxyfluorosilane as the source of the fluoride and dodecylamine as templates. The TiO2 loaded on the hydrophobic MS(F) (TiO2/MS(F)) exhibited the efficient photocatalytic performance for the degradation of alcohols (iso-butanol) diluted in water. The photocatalytic reactivity for the degradation increased with increasing the content of fluoride ions on these photocatalysts. The hydrophobic mesoporous surface is suitable as the photocatalytic reaction field for the degradation of organic compounds diluted water.