Effects of processing parameters on 3D structural ordering and optical properties of inverse opal photonic crystals produced by atomic layer deposition

Abstract

Vertical convective self‐assembly has been extensively used for the preparation of direct photonic crystals, which can be later infiltrated with a more stable material, such as oxide ceramics, by atomic layer deposition. However, the relationship between the self‐assembly parameters of the direct photonic crystals and the optical properties of the inverse opal photonic crystals remains elusive. In this work, the effect of different experimental parameters on the 3D structure and the density of defects of polystyrene direct photonic crystals produced by vertical convective self‐assembly was assessed. Self‐assembly was investigated using deionized water as media with polymer particles’ concentrations up to 2 mg/mL; temperatures of 40, 50, and 80°C; and relative humidity of 45%, 70%, and 90%. The 3D structure of the resultant direct photonic materials was characterized by the combination of scanning electron microscopy and image analysis, and their optical properties were assessed by reflectance measurements. These results were correlated with the performance of oxide‐based inverse opal photonic crystals produced by the controlled infiltration of the former direct photonic crystals by atomic layer deposition (ALD). It was found that the thickness increased with the concentration of polystyrene particles, while the photonic structure ordering is dependent on the synergy between humidity and temperature. Results also showed higher defects population with increasing evaporation temperature and decreasing relative humidity.

Tailoring Disorder and Quality of Photonic Glass Templates for Structural Coloration by Particle Charge Interactions

“…In these cases, the evaporation rate during the film drying process was significantly faster than for the base particles (Figure ). Generally, slower water evaporation generates less cracks compared to faster evaporation rates . Here, the fast evaporation is related to the suggested deposition process in Figure b, which is governed by the sedimentation of agglomerated particles.…”

“…Generally, slower water evaporation generates less cracks compared to faster evaporation rates. 59 Here, the fast evaporation is related to the suggested deposition process in Figure 4b, which is governed by the sedimentation of agglomerated particles. Due to the resulting loose packing and high porosity, less interstitial water is trapped between the agglomerates.…”

Bright Structural Color and High Hydrophobic Properties of Photonic Crystal Films on the Ceramic Glaze Layer via Vertical Deposition Self‐Assembly Method

“…Simultaneously, with a high concentration of SiO 2 microspheres suspension, the layer number of photonic crystals increases, which causes abundance defects and inhomogeneous hybrid structure of glaze and SiO 2 microspheres, and then results in films falling off after sintered, indicating that the high concentration is inappropriate to structural color films. Moreover, when the SiO 2 concentration is too high or too low, the number of point defects and line defects significantly increases [25] . Therefore, it is helpful to prepare large‐area ordered structural color films by appropriately adjusting the concentration of SiO 2 microspheres suspension.…”

“…Moreover, when the SiO 2 concentration is too high or too low, the number of point defects and line defects significantly increases. [25] Therefore, it is helpful to prepare large-area ordered structural color films by appropriately adjusting the concentration of SiO 2 microspheres suspension.…”

Unraveling the role of shell thickness and pore size on the mechanical properties of ceramic‐based macroporous structures

“…Whilst most of the research efforts have been focused on polymeric and SiO 2 inverse opals, investigations have also been performed on metallic, 26,27 carbon-based, 28 siliconbased, 29 and ceramic inverse opals. 20,22,[30][31][32][33][34][35] A variety of ceramic-based inverse opal macroporous structures have been reported such as silica, 17,36,37 silicon carbide, 38 titania, 20,39,40 alumina, 35,41,42 zirconia, 40 yttria-stabilized zirconia 18 and mullite. 22 When compared to metals and polymers, ceramics generally present a higher chemical, microbiological and thermal stability.…”