Solution heteroepitaxial growth of dendritic SnO 2 /TiO 2 hybrid nanowires
- PDF / 551,829 Bytes
- 7 Pages / 584.957 x 782.986 pts Page_size
- 48 Downloads / 177 Views
Yee Yan Tay and Huey Hoon Hng School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore
Hong Jin Fana) Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore (Received 26 January 2011; accepted 21 March 2011)
We exploit a facile synthetic route to fabricate dendritic SnO2/TiO2 nanodentrites with a twofold point symmetry by a combination of vapor transport deposition method for the SnO2 nanowire backbones and subsequent hydrothermal heteroepitaxial growth of TiO2 nanorod branches. As a result of the good lattice matching and same rutile crystal structures between SnO2 and TiO2, an interface epitaxy is established accounting for the high symmetry. Proof-of-principle demonstration of the function in photoelectrochemical water splitting is presented.
I. INTRODUCTION
Growth of nanoarchitectures with a tunable dimension and structure complexity represents a challenge in the field of nanoscience and is an essential step toward the realization of multifunctionality of nanosystems.1–4 In particular, one-dimensional semiconductor heterostructures have gained increasing attention in recent years because of their synergic physical properties that originate but differ from the individual constituents and, thus, are more useful for constructing new-concept nanoscale optoelectronic devices.5–9 Currently, the typical synthetic methods for high-quality monocrystalline heterostructures are based on vapor phase epitaxial growth such as metalorganic vapor phase epitaxy and molecule beam epitaxy, which utilizes the moderate mismatches between the two different materials and involves the vapor–liquid–solid process. In contrast to the vapor phase epitaxy, solution epitaxial growth of heterostructures is of particular interest because of its simplicity of fabrication and low cost, although it is more challenging to satisfy the lower mismatche requirement.10–12 In the past few years, various oxide semiconductor heterostructures such as SnO2/ Fe2O3,13 ZnO/TiO2,14 and SnO2/TiO215,16 have been investigated because of their wide applications. Among them, TiO2 and SnO2 are well-known wide direct-bandgap materials and possess application potential in photoelectrochemical (PEC) water splitting,17 dye-sensitized solar cells,18 gas sensing,19 and so on. It has been previously a)
Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/jmr.2011.99 2254
J. Mater. Res., Vol. 26, No. 17, Sep 14, 2011
http://journals.cambridge.org
Downloaded: 31 Aug 2014
demonstrated that TiO2 coupling with SnO2 semiconductor can facilitate the charge separation and transportation because of the proper band edge alignment and higher electron mobility of SnO2 and thus boost up the photoconversion efficiency.15,16 Although various methods have been explored for the controlled synthesis of nanostructures of both SnO2 and TiO2 individually, a high level of structural and morphological control for the SnO2/TiO2 heterostructur
Data Loading...
