Crystallographic Alignment of ZnO Nanorod Arrays on Zn₂GeO₄ Nanocrystals: Promising Lattice-Matched Substrates

Abstract

We demonstrated that ternary Zn2GeO4 crystals could be used as potential lattice-matched substrates for ZnO nanorod array growth. Single-crystalline Zn2GeO4 nanowires were used as substrates for crystallographic alignment of ZnO nanorod arrays. Structural characterization verified the heteroepitaxial growth between the ZnO c-plane and Zn2GeO4 side facets, which was attributed to the small lattice mismatches. The semiconducting Zn2GeO4 crystals are of potential interest as novel alternative substrates for ZnO nanorod array growth.

Synthesis, characterization and electrical properties of hybrid Zn2GeO4–ZnO beaded nanowire arrays

“…The crystalline Zn 2 GeO 4 /ZnO beaded nanowires serve as an ideal substrate for ZnO nanobranches growth. The [110] crystallography planes of growth Zn 2 GeO 4 beads on /100S faced plane of ZnO allow epitaxial growth of ZnO nanowires [27].…”

“…Recently, the axial growth mechanism of Zn 2 GeO 4 -ZnO nanowire heterojunction and crystallographic alignment of ZnO nanorod arrays on Zn 2 GeO 4 nanocrystal have been studied [26,27]. The most conventional way to synthesize the ternary oxide nanowire in chemical vapor deposition (CVD) technique is the high temperature co-evaporation of either the mixture of the constituent powders or dual-source deposition onto appropriate substrates [28,29].…”

Rational growth of ternary Zn2GeO4 nanorods and self-assembled hierarchical nanostructures

“…Zn 2 GeO 4 nanorods were also shown to be more efficient than TiO 2 and bulk Zn 2 GeO 4 in degradation of organic pollutants in water [23], and could be widely used in decomposition of water, benzene and other volatile aromatic pollutants under ambient conditions [24][25][26]. Besides, Yan et al reported that the novel ternary Zn 2 GeO 4 crystals can be used as lattice-matched substrates for ZnO nanorod array growth [27]. Importantly, the rhombohedral phase of Zn 2 GeO 4 nanobelts, hexagonal nanorods, and mesoporous structures display an improved photocatalytic reduction of CO 2 into renewable hydrocarbon fuel [28][29][30].…”

Axial growth of Zn2GeO4/ZnO nanowire heterojunction using chemical vapor deposition

“…Being able to realize surface passivation and charge separation at nanoscale, radial heterojunctions, such as core/shell nanowires, have been applied in the fabrication of field effect transistor (FET) [8], light-emitting diode (LED) [9], solar cell [10,11], etc. Recently reported biaxial [12], coaxial [12] and hierarchical branched [13][14][15] semiconducting nanowire heterostructures further broaden the field of radial heterojunctions. Regarding axial heterojunctions synthesis, however, studies are relatively few compared to the radial counterpart due to more stringent requirements of crystallographic relationships and reactant atmospheres during growth.…”

“…In the oxide semiconductor system, a series of oxide nanowire superlattices were also grown, such as In 2 O 3 (ZnO) m (m¼4, 5) [31,32], Zn doped In 2 O 3 -SnO 2 [33], and InGaO 3 (ZnO) m (m¼3, 5) [34], corresponding to the natural superlattice structures in bulk oxide compounds. With the recent progress made on ternary oxide nanowire synthesis [35], there are increasing interests in forming ternary/binary oxide nanowire heterojunctions to investigate their unique physical properties [15,36,37]. So far, there are only few reports about axial growth of ternary/binary oxide heterojunctions [38], indicating the great challenge in axial growth for this kind of complex system.…”