Synthesis, characterization and photocatalytic properties of novel zinc germanate nano-materials

详细信息    查看全文

• 作者：Venkata Bharat Ram Boppana^a ; Nathan D. Hould^a ; Raul F. Lobo ; ^a ; ^{lobo@udel.edu"" rel=""nofollow}
• 关键词：Photocatalysis ; Photocatalyst ; Zn₂GeO₄ ; Morphology ; Hydrothermal ; Methylene blue
• 刊名：Journal of Solid State Chemistry
• 出版年：2011
• 出版时间：May 2011
• 年：2011
• 卷：184
• 期：5
• 页码：1054-1062
• 全文大小：1052 K

文摘

We report the first instance of a hydrothermal synthesis of zinc germanate (Zn₂GeO₄) nano-materials having a variety of morphologies and photochemical properties in surfactant, template and catalyst-free conditions. A systematic variation of synthesis conditions and detailed characterization using X-ray diffraction, ultraviolet–visible diffuse reflectance spectroscopy, Raman spectroscopy, electron microscopy, X-ray photoelectron spectroscopy and small angle X-ray scattering led to a better understanding of the growth of these particles from solution. At 140 °C, the zinc germanate particle morphology changes with pH from flower-shaped at pH 6.0, to poly-disperse nano-rods at pH 10 when the Zn to Ge ratio in the synthesis solution is 2. When the Zn to Ge ratio is reduced to 1.25, mono-disperse nano-rods could be prepared at pH 7.5. Nanorod formation is also independent of the addition of cetyltrimethylammonium bromide (CTAB), in contrast to previous reports. Photocatalytic tests show that Zn₂GeO₄ nano-rods (by weight) and flower shaped (by surface area) are the most active for methylene blue dye degradation among the synthesized zinc germanate materials.