title: Preparation of anatase/rutile mixed-phase titania nanoparticles for dye-sensitized solar cells.
abstract: Acid-labile high surface mesoporous ZnO/Zn(OH)2 composite material is used as a novel hard template for the preparation of mesoporous amorphous TiO2. The template-free amorphous TiO2 material is then thermally crystallized at suitable temperature to control the relative ratio of anatase and rutile phases in a particle. Four different anatase/rutile (AR) mixed-phase TiO2 nanoparticles (AR-3, AR-15, AR-20, and AR-23 denoted for the samples of 3%, 15%, 20%, and 23% rutile phase, respectively) are prepared and characterized by powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM). The coexistence of anatase and rutile phases in a TiO2 nanoparticle is visually confirmed by HRTEM analysis. These mixed-phase TiO2 nanoparticles are examined as candidates for photoelectrodes of dye-sensitized solar cells (DSSCs). The J-V curves and IPCE spectra for the DSSCs prepared from the mixed-phase TiO2 nanoparticles are obtained, and their photovoltaic properties are investigated. The photo-conversion efficiency (eta) indicates the highest value of 5.07% for AR-20. The synergistic effect of coexisting anatase and rutile phases with an optimal ratio in a TiO2 nanoparticle of AR-20 for an efficient interfacial transfer of photo-generated electrons is likely to lead to the highest efficiency among the AR-n samples.
authors.affiliation: Department of Chemistry and Protein Research Center for Bio-Industry, Hankuk University of Foreign Studies, Yongin 449-791, Korea.
authors.forename: Yong-Kyung
authors.initials: YK
authors.lastname: Hwang
authors.forename: Sung Soo
authors.initials: SS
authors.lastname: Park
authors.forename: Jun-Heok
authors.initials: JH
authors.lastname: Lim
authors.forename: Yong Sun
authors.initials: YS
authors.lastname: Won
authors.forename: Seong
authors.initials: S
authors.lastname: Huh
mesh_terms: D004396:Coloring Agents; D053768:Metal Nanoparticles; D046529:Microscopy, Electron, Transmission; D033362:Powder Diffraction; D014025:Titanium / Q000737:chemistry*
chemical_list: D004396:Coloring Agents; C009495:titanium dioxide; D014025:Titanium