Materials Science and Engineering Program, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
J Environ Manage. 2016 Feb 1;167:99-104. doi: 10.1016/j.jenvman.2015.11.028. Epub 2015 Nov 22.
Titania-functionalized graphene oxide (T-F GO), synthesized by a sol-gel process, was used as a highly efficient material to remove phosphate ions from the simulated wastewater. X-ray diffraction spectra, Fourier transform infrared spectra and scanning electron micrographs of T-F GO confirmed that titania particles were successfully grown on graphene oxide (GO) surface. The phosphate ion adsorption capacities of GO, titania and T-F GO as a function of the contact time and the pH were investigated by a UV-visible spectrophotometer. Results showed that T-F GO could absorb phosphate ions better than titania and GO could. This indicated the synergistic effect between titania and GO in the phosphate ion adsorption. The pH increment lowered the absorption capacities due to increasing the repulsion between phosphate anions and the charges on the T-F GO surface, whereas the addition of sodium ions increased the adsorption capacities. Also, phosphate ions were absorbed by specific sites of T-F GO and formed a monolayer on its surface. Finally, the maximum adsorption capacity of T-F GO was 33.11 mg/g at pH 6, much higher than those of GO and titania. Therefore, T-F GO could be a promising material to remove phosphate ions from wastewater in the future.
采用溶胶-凝胶法制备的四钛酸功能化氧化石墨烯（T-F GO）作为一种高效材料，用于从模拟废水中去除磷酸根离子。T-F GO 的 X 射线衍射谱、傅里叶变换红外光谱和扫描电镜图证实，钛酸粒子成功地生长在氧化石墨烯（GO）表面上。通过紫外可见分光光度计研究了 GO、TiO2 和 T-F GO 作为吸附剂的吸附时间和 pH 值对磷酸根离子吸附性能的影响。结果表明，T-F GO 比 TiO2 和 GO 更能有效地吸附磷酸根离子，这表明 TiO2 和 GO 在磷酸根离子吸附中具有协同作用。pH 值的升高降低了吸附容量，这是由于磷酸根阴离子与 T-F GO 表面电荷之间的排斥作用增加，而钠离子的加入则增加了吸附容量。此外，磷酸根离子被 T-F GO 的特定位置吸附，并在其表面形成单层。最终，T-F GO 在 pH 值为 6 时的最大吸附容量为 33.11 mg/g，远高于 GO 和 TiO2。因此，T-F GO 有望成为未来从废水中去除磷酸根离子的一种有前途的材料。
