title: One-step preparation of single-crystalline beta-MnO2 nanotubes.
abstract: Single-crystal beta-MnO(2) nanotubes with diameters in the range 200-500 nm and lengths up to several micrometers were successfully prepared by a simple hydrothermal method through oxidizing MnSO(4) with NaClO(3) in the presence of poly(vinyl pyrrolidone) (PVP). It was found that the formation process of beta-MnO(2) nanotubes included two primary evolution stages over time: (1) the MnOOH nanoparticles initially formed in the hydrothermal system and anisotropic growth to nanorods and nanorod aggregates, and (2) the MnOOH nanorods transformed into beta-MnO(2) tubular structure and grown into beta-MnO(2) nanotubes due to continuous growth through a dissolution-recrystallization process eventually. Based on a series of experimental analysis, the formation mechanism of these nanostructures was discussed briefly. The present study has enlarged the family of nanotubes available and offers a possible new, general route to one-dimensional single-crystalline nanotubes of other materials.
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education, Jinan, Shandong 250100, People's Republic of China.
authors.forename: Deshan
authors.initials: D
authors.lastname: Zheng
authors.forename: Sixiu
authors.initials: S
authors.lastname: Sun
authors.forename: Weiliu
authors.initials: W
authors.lastname: Fan
authors.forename: Haiyun
authors.initials: H
authors.lastname: Yu
authors.forename: Chunhua
authors.initials: C
authors.lastname: Fan
authors.forename: Guangxiang
authors.initials: G
authors.lastname: Cao
authors.forename: Zhilei
authors.initials: Z
authors.lastname: Yin
authors.forename: Xinyu
authors.initials: X
authors.lastname: Song