title: Fabrication of SiO2/TiO2 double-shelled hollow nanospheres with controllable size via sol-gel reaction and sonication-mediated etching.
abstract: Size-controllable double-shell SiO2/TiO2 hollow nanoparticles (DS HNPs) were fabricated using a simple sol-gel reaction and sonication-mediated etching. The size of the DS HNPs was controlled using SiO2 core templates of various sizes. Moreover, monodisperse DS HNPs were produced on a large scale (10 g per 1 batch) using the sol-gel method. The surface area and porosity of intrashell and inner-cavity pores were measured by Brunauer-Emmett-Teller analysis. As a result, 240 nm DS HNPs (240 DS HNPs) exhibited the highest surface area of 497 m(2) g(-1) and a high porosity. Additionally, DS HNPs showed excellent light-scattering ability as a scattering layer in dye-sensitized solar cells due to their structural properties, such as a composite, double-shell, hollow structure, as well as intrashell and inner cavity pores. The DSSCs incorporating 240 DS HNPs demonstrated an 18.3% enhanced power conversion efficiency (PCE) compared to TiO2 nanoparticles.
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University , 599 Gwanangno, Gwanakgu, Seoul 151-742, Korea.
authors.forename: Jungsup
authors.initials: J
authors.lastname: Lee
authors.forename: Sun Hye
authors.initials: SH
authors.lastname: Hwang
authors.forename: Juyoung
authors.initials: J
authors.lastname: Yun
authors.forename: Jyongsik
authors.initials: J
authors.lastname: Jang
keywords: double-shell hollow nanoparticles; dye-sensitized solar cell; light scattering; porous nanoparticle; sol−gel method