Controllable Synthesis of Zn₂GeO₄Nanorods for Photocatalytic Reduction of Aqueous Cr(VI) and Oxidation of Organic Pollutants

Abstract

Zn 2 GeO 4 nanorods were successfully synthesized by a simple hydrothermal method. The composition, morphology, and optical properties of as-synthesized Zn 2 GeO 4 samples were characterized by X-ray diffraction, scan electron microscopy, and UV-vis diffuse reflectance spectra. The photocatalytic properties of Zn 2 GeO 4 nanorods were evaluated by the reduction of Cr(VI) and oxidation of organic pollutants in aqueous solution. The effects of solution pH on Cr(VI) reduction by Zn 2 GeO 4 nanorods were studied in detail. The results indicated that the efficiency of Cr(VI) reduction was highest at pH 5.96. Moreover, Zn 2 GeO 4 nanorods also showed excellent photocatalytic ability for the oxidation of organic pollutants such as rhodamine B and 4-nitrophenol.

Visible Light Active Single-Crystal Nanorod/Needle-like α-MnO2@RGO Nanocomposites for Efficient Photoreduction of Cr(VI)

“…Among all of these, photocatalytic removal of Cr­(VI) by semiconductor photocatalysts is considered as an attractive and gainful method. In the photocatalytic reduction process, Cr­(VI) is reduced to Cr­(III) which is nontoxic and plays a vital role in plant and animal metabolism. , Therefore, semiconductor photocatalysts such as TiO 2 , ZnO, SnS 2 , ZnGeO 4 , Sn 2 S 3 , and Bi 2 WO 6 have been reported for the reduction of Cr­(VI) to Cr­(III). − …”