Rapid fabrication and characterization of SiO2-Fe2O3 heterogeneous metamaterial via one-step self-assembly process

SiO₂-Fe₂O₃ heterogeneous metamaterial was fabricated by one-step self-assembly process. The micro-morphology and optical properties of the SiO₂-Fe₂O₃ heterogeneous metamaterials were characterized by scanning electron microscope (SEM) and UV/Vis/NIR spectrophotometer respectively. The crystal phase of the calcined Fe₂O₃ powders was characterized by X-ray diffraction (XRD). The influences of the concentration of SiO₂ suspension and voltage on heterogeneous metamaterials are discussed. The model of SiO₂-Fe₂O₃ heterogeneous photonic crystal was established, and the wavelength of the bandgap center was simulated and analyzed. The results show that the ordered SiO₂-Fe₂O₃ heterogeneous metamaterial can be successfully obtained by a one-step self-assembly process with no voltage when the concentration of SiO₂ suspension is 3% (in a short time). In the suspension system, the voltage is not beneficial to the self-assembly process, and even destroys the electrode cathode. As can be seen from transmission spectra, the as-prepared samples have three bandgaps, and the absorption peaks are obvious in the near infrared range (12351419 nm). In this paper, we show that the application of this composite system can avoid dependence on the ITO electrode material.