title: Fabrication of Photocatalytic Paper Using TiO2Nanoparticles Confined in Hollow Silica Capsules.
abstract: TiO2nanoparticles (NPs) encapsulated in hollow silica spheres (TiO2@HSSs) show a shielding-effect that can insulate photocatalytically active TiO2NPs from the surrounding environment and thus prohibit the self-degradation of organic support materials under ultraviolet (UV)-light irradiation. In this study, photocatalytically active papers were fabricated by combining TiO2@HSS and cellulose fibers, and their photocatalytic activities and durability under UV-light irradiation were examined. The yolk-shell nanostructured TiO2@HSS, which has an ample void space between inner TiO2NPs and an outer silica shell, was synthesized using a facile single-step method utilizing an oil-in-water microemulsion as an organic template. The thus-prepared TiO2@HSS particles were deposited onto a cellulose paper either by the chemical adhesion process via ionic bonding or by the physical adhesion process using a dual polymer system. The obtained paper containing TiO2@HSS particles with high air permeability exhibited a higher photocatalytic activity in the photocatalytic decomposition of volatile organic compounds than unsupported powdery TiO2@HSS particles because of the uniform dispersion on the paper with a reticular fiber network. In addition, the paper was hardly damaged under UV-light irradiation, whereas the paper containing naked TiO2NPs showed a marked deterioration with a considerably decreased strength, owing to the ability of the silica shell to prevent direct contact between TiO2and organic fibers. This study can offer a promising method to fabricate photocatalytically active papers with a photoresistance property available for real air cleaning.
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.|Paper Technology Center, Ehime Institute of Industrial Technology , 127 Mendori-cho, Shikokuchuo, Ehime 799-0113, Japan.
authors.forename: Kensei
authors.initials: K
authors.lastname: Fujiwara
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.|Unit of Elements Strategy Initiative for Catalysts & Batteries (ESICB), Kyoto University , Katsura, Kyoto 615-8520, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Kuwahara
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Sumida
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.|Unit of Elements Strategy Initiative for Catalysts & Batteries (ESICB), Kyoto University , Katsura, Kyoto 615-8520, Japan.
authors.forename: Hiromi
authors.identifier: 0000-0003-1796-5776
authors.initials: H
authors.lastname: Yamashita