Chemistry Department, Faculty of Science, Sohag University, Sohag 82524, Egypt.
Chemistry Department, Faculty of Science, King Abdulaziz University, 21589 Jeddah, P.O. Box 80203, Saudi Arabia.
J Nanosci Nanotechnol. 2019 Aug 1;19(8):5177-5188. doi: 10.1166/jnn.2019.16827.
In this research, cetyltetraethyl ammonium bromide template assisted microwave procedure was utilized to synthesize reduced graphene oxide-zirconia (rGO-ZrO₂) nanocomposites by varying the rGO composition (1, 2, 5 and 10 wt%). The physico-chemical characteristics of the nanocomposites were studied using X-ray diffraction (XRD), Raman, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), diffusive reflectance ultraviolet-visible (DRUV-vis), X-ray photoelectron spectroscopy (XPS) and N2-physisorption techniques. The results from XRD, Raman and DSC studies indicate that the increase in rGO concentration resulted in the delay in ZrO₂ crystallization temperature and alteration of ZrO₂ phase from monoclinic to tetragonal due to an effective incorporation of rGO nanosheets in ZrO₂ structure. The rGO loading also have an influence in the morphology of nanocomposites, as sample with 10 wt% rGO possessed unique monolith like morphology with macro pores. All the nanocomposites were utilized as photocatalysts for degradation of crystal violet dye in visible light irradiation. The rGO-ZrO₂ nanocomposites showed high reaction rates; the nanocomposite with 5 wt% rGO showed the superior photocatalytic performance as this sample possessed low band gap energy, high surface area, pore volume and presence of surface rGO-ZrO₂ interactive species as well as the reactive -OH groups. In addition, the synthesized nanocomposites exhibited excellent recyclability for photocatalytic degradation.
在这项研究中，采用十六烷基四乙溴化铵模板辅助微波法，通过改变 rGO 含量（1、2、5 和 10wt%），合成还原氧化石墨烯-氧化锆（rGO-ZrO₂）纳米复合材料。采用 X 射线衍射（XRD）、拉曼、差示扫描量热法（DSC）、扫描电子显微镜（SEM）、漫反射紫外-可见分光光度计（DRUV-vis）、X 射线光电子能谱（XPS）和 N2 吸附技术对纳米复合材料的物理化学性质进行了研究。XRD、拉曼和 DSC 研究结果表明，rGO 浓度的增加导致 ZrO₂ 结晶温度延迟，ZrO₂ 相从单斜相转变为四方相，这是由于 rGO 纳米片有效地掺入了 ZrO₂ 结构。rGO 的负载量也对纳米复合材料的形态有影响，10wt%rGO 的样品具有独特的块状形貌和大孔。所有的纳米复合材料都被用作可见光照射下降解结晶紫染料的光催化剂。rGO-ZrO₂ 纳米复合材料表现出较高的反应速率；5wt%rGO 的纳米复合材料表现出较好的光催化性能，因为该样品具有较低的带隙能、较高的比表面积、孔体积和表面 rGO-ZrO₂ 相互作用物种以及反应性 -OH 基团。此外，所合成的纳米复合材料在光催化降解中表现出优异的可回收性。
