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Graphical abstract Highlights • The speed of the preparation of SiO 2 -Fe 2 O 3 heterogeneous metamaterials was successfully improved by the one-step method. • Ordered SiO 2 -Fe 2 O 3 heterogeneous metamaterials can be prepared via the one-step method without applying a voltage. • There is a photonic band gap in the infrared range. Abstract SiO 2 -Fe 2 O 3 heterogeneous metamaterial was fabricated by one-step self-assembly process. The micro-morphology and optical properties of the SiO 2 -Fe 2 O 3 heterogeneous metamaterials were characterized by scanning electron microscope (SEM) and UV/Vis/NIR spectrophotometer respectively. The crystal phase of the calcined Fe 2 O 3 powders was characterized by X-ray diffraction (XRD). The influences of the concentration of SiO 2 suspension and voltage on heterogeneous metamaterials are discussed. The model of SiO 2 -Fe 2 O 3 heterogeneous photonic crystal was established, and the wavelength of the bandgap center was simulated and analyzed. The results show that the ordered SiO 2 -Fe 2 O 3 heterogeneous metamaterial can be successfully obtained by a one-step self-assembly process with no voltage when the concentration of SiO 2 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 (1235˜1419 nm). In this paper, we show that the application of this composite system can avoid dependence on the ITO electrode material. [ABSTRACT FROM AUTHOR]

• The prepared Sn 4 Sb 6 S 13 (TAS) thin film on PAA at different deposition temperatures results an evolution in the crystal sizes and shapes at the surface. • XRD and Raman patterns presented an increase in the peak intensity and a change in the peaks position toward higher energy indicating the crystalline quality enhancement. • The average R% spectra decreased significantly from 71.6% for the PAA layer to 59.9%, indicating the large absorbance of the deposited compound on PAA substrates. • The average reflectivity of TAS/PAA multilayered structure increases significantly from 59.9%–61.4% by increasing substrate temperature from 30 to 140 °C, owing to an improvement in the film crystallization. • The refractive index (n), extinction coefficient (k), the real and imaginary dielectric constants, as well as the thickness of TAS/PAA multilayers were estimated from the ellipsometric measurements. In this study, the Sn 4 Sb 6 S 13 (TAS) nanocrystals were grown on the porous anodic alumina (PAA) templates through the vacuum thermal evaporation process at different deposition temperatures. The influence of deposition temperature on the microstructural and optical properties of TAS/PAA was investigated systematically. As the substrate temperature is increased, crystallite size increases while the strain and the dislocation density decrease. An improvement of the crystallinity is deduced from Raman spectra and X-Ray diffraction (XRD) patterns. The homogeneous distribution of TAS nanocrystals on PAA substrates was observed from surface morphology by using atomic force microscopy (AFM) and scanning electron microscope (SEM). The average reflectance of TAS/PAA films decreased significantly from 77 % to 60 % in the visible and near-infrared spectral regions, indicating the large absorbance of the deposited thin film. The optical parameters and thickness of TAS/PAA layers were estimated on the basis of spectroscopic ellipsometry measurements. [ABSTRACT FROM AUTHOR]