Abstract In this study (1-x)SiO2-xCoFe2O4 (x = 0,0.2,0.4,0.8,1) nanocomposites were synthesized using the sol-gel auto-combustion route and structure, morphology, thermal, optical and magnetic properties of as-prepared samples were investigated. X-ray diffraction followed by Williamson-Hall analysis revealed the formation of pure cobalt ferrite (CFO) nanoparticles and SiO2-CFO nanocomposites. Scanning electron microscope (SEM) images showed that SiO2 matrix serves as a physical barrier to control the morphology and size of cobalt ferrite nanoparticles and prevents nanoparticles agglomeration. Diffuse reflectance UV–Vis spectroscopy analysis showed that the optical band-gap of SiO2-CFO nanocomposites decreases from 1.23 eV to 1.12 eV with increasing the concentration of cobalt. Finally, the vibrating sample magnetometer (VSM) analysis that as cobalt ferrite content increases, the magnetic properties of nanocomposites improved. These nanocomposites could be applicable as a magnetic photo-catalysts.

中文翻译：

---

SiO2-CoFe2O4 纳米复合材料的一步燃烧合成及其结构、热、光学和磁性能表征

摘要 本研究采用溶胶-凝胶自燃路线合成了 (1-x)SiO2-xCoFe2O4 (x = 0,0.2,0.4,0.8,1) 纳米复合材料，其结构、形貌、热学、光学和磁学性质如下： - 对制备的样品进行了研究。X 射线衍射和 Williamson-Hall 分析揭示了纯钴铁氧体 (CFO) 纳米颗粒和 SiO2-CFO 纳米复合材料的形成。扫描电子显微镜 (SEM) 图像显示 SiO2 基质作为物理屏障来控制钴铁氧体纳米粒子的形态和尺寸并防止纳米粒子团聚。漫反射紫外-可见光谱分析表明，随着钴浓度的增加，SiO2-CFO 纳米复合材料的光学带隙从 1.23 eV 降低到 1.12 eV。最后，振动样品磁强计（VSM）分析表明，随着铁氧体钴含量的增加，纳米复合材料的磁性能提高。这些纳米复合材料可用作磁性光催化剂。