title: Hydrothermal synthesis of single-crystalline perovskite PbTiO3 nanosheets with dominant (001) facets.
abstract: Single-crystalline tetragonal perovskite lead titanate (PbTiO3) nanosheets with dominant (001) facets have been successfully synthesized by employing layered K2Ti6O13 nanofibers as titanium sources. The as-prepared PbTiO3 nanosheets were characterized by means of X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, and selected-area electron diffraction. In order to understand the formation mechanism of the PbTiO3 nanosheets, a series of time-dependent experiments were performed. Because of the substitution of Pb(2+) ions for K(+) ions, the TiO6 octahedral lamellas exfoliate from the layered K2Ti6O13 crystal structure. Then the exfoliated TiO6 octahedral lamellas as templates transform to lamellar PbTiO3 species by reacting with the dehydrated Pb(2+) ions. With hydrothermal treatment prolongation, the lamellar PbTiO3 species crystallize to single-crystalline PbTiO3 nanosheets. Moreover, the thickness of the synthesized single-crystalline PbTiO3 nanosheets can be tailored in the range of 10-50 nm by controlling the hydrothermal treatment time. In addition, the band gap and the optoelectronic properties of the single-crystalline PbTiO3 nanosheets are investigated by UV-vis absorption and photoluminescence.
authors.affiliation: State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, and Key Laboratory of Advanced Materials and Applications for Battery of Zhejiang Province, Zhejiang University , Hangzhou 310027, China.
authors.forename: Shiqi
authors.initials: S
authors.lastname: Deng
authors.forename: Gang
authors.initials: G
authors.lastname: Xu
authors.forename: Huiwen
authors.initials: H
authors.lastname: Bai
authors.forename: Lingling
authors.initials: L
authors.lastname: Li
authors.forename: Shan
authors.initials: S
authors.lastname: Jiang
authors.forename: Ge
authors.initials: G
authors.lastname: Shen
authors.forename: Gaorong
authors.initials: G
authors.lastname: Han