A Template-Free Solution Route for the Synthesis of Well-Formed One-Dimensional Zn₂GeO₄ Nanocrystals and Its Photocatalytic Behavior

Abstract

Well-defined Zn2GeO4 hexagonal nanorods and nanofibers with high aspect ratios have been readily realized in high yield via a simple and general hydrothermal synthesis method free of any surfactant or template. Field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectrometry (EDX), powder X-ray diffraction (XRD), and ultraviolet-visible light diffuse reflectance spectroscopy (UV-vis DRS) revealed a unique hexagonal-prism-shaped one-dimensional (1-D) structure, surface features, anisotropic crystal growth, and crystal phase of Zn2GeO4. Detailed investigations indicated that the prismatic Zn2GeO4 nanocrystals are uniform single crystal with the longitudinal direction along the [001] and were dominated by (110) and (110) surfaces. The addition of increasing amounts of NaOH was found to facilitate the morphology transition from a hexagonal nanorod shape to a hexagonal fiber shape. As an important wide-band-gap photocatalyst, the products of regular Zn2GeO4 nanocrystals with a hexagonal 1-D structure exhibit superior photocatalytic activities for the photocatalytic decomposition of water-methanol solution to hydrogen under UV irradiation.

Fabrication of well-shaped Sr2KTa5O15 nanorods with a tetragonal tungsten bronze structure by a flux method for artificial photosynthesis

“…This result implies that the mixture of Sr 2 KTa 5 O 15 nanoplates and nanorods containing an unknown impurity, even with the highest BET specific surface area, exhibits activity in favor of water splitting and not for the photocatalytic conversion of CO 2 by H 2 O. Increasing the calcination temperature from 1223 K to 1373 K led to a slight decrease in the photocatalytic activity for the formation rate of CO, which might be due to the decrease in the BET specific surface area and the increase in the length of the nanorods [31]. Overall, these results indicate that the Sr 2 KTa 5 O 15 nanorods prepared using a flux method show high formation rates of CO and good selectivity toward CO evolution.…”

Enhanced photodegradation activity of methyl orange over Z-scheme type MoO3–g-C3N4 composite under visible light irradiation

“…Actually, band potential difference was considered as an important reason of the higher photoactivities of BiOCl and Zn 2 GeO 4 than that of P25. 57,58 However, for composite photocatalysts, the positive effect of charge separation is great enough to control the photocatalytic reaction. The effect of the change in redox ability resulting from the charge migration is usually neglected.…”

Preparation of flower-like ZnO architectures assembled with nanosheets for enhanced photocatalytic activity

“…Three-dimensional (3D) hierarchical nanostructures, assembled by 1D and 2D nanoscale building blocks including nanowires [1], nanorods [2] and nanosheets [3], have received special attention due to their unique optical [4,5] and electrical properties [6,7]. Up to now, many functional materials with novel architectures such as TiO 2 , ZnO, SnO 2 and other metal oxides have been reported [8][9][10][11].…”