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In this study, Taylor-vortex reactor was adopted to synthesize silica nanoparticles from sodium silicate solution and carbon dioxide. The outstanding advantages of the reactor have been demonstrated by comparing the synthesis results of silica nanoparticles by Erlenmeyer reactor. The results showed that silica particles synthesized from Taylor-vortex reactor are smaller in size than silica particles synthesized from the Erlenmeyer reactor. SEM images and histogram of particle size distribution obtained from experiments clearly exhibited that the concentration of SiO2 in the solution, reaction temperature, and rotation speed of the cylinder significantly affected morphology as well as size of the silica particles.

This study fabricated a functional coating layer for transparent electrodes using antimony tin oxide nanopowder. The wet grinding method was employed to create a stable dispersion solution of antimony tin oxide nanopowder with aminopropyl tri-methoxysilane and acetyl acetone as primary dispersing agents. Various concentrations of these dispersing agents were used to determine optimal conditions, followed by a gel reaction to form a stable solution. The primary objective was to provide a viable alternative to indium-based transparent electrodes, specifically indium tin oxide, by incorporating antimony oxide. This approach not only addresses limitations associated with indium, but also enhances mechanical properties. The methodology involves the utilization of antimony tin oxide nanopowder and various solvents including ethanol and aforementioned dispersing agents to create a stable antimony tin oxide sol through wet grinding. Effects of dispersant concentration and milling time on the secondary particle size of the antimony tin oxide sol were thoroughly evaluated. Furthermore, this study examined sheet resistance of resulting coating layers by conducting a comparative analysis between antimony tin oxide and indium tin oxide under similar conditions. Findings of this study meticulously detailed in subsequent sections of the manuscript provide valuable insights into optimizing the entire process, encompassing synthesis, coating, heat treatment, and the production of high-quality transparent conductive coatings. These techniques and outcomes can significantly contribute to the development of more sustainable and cost-effective alternatives to traditional indium-based transparent electrodes.

Modeling of adsorption phenomena was carried out for core-shell adsorbents with spherical, cylindrical, and slab-type morphologies. Numerical solutions of adsorbates in the adsorber could be obtained as a function of time by solving coupled diffusion equations to take account of the inert-core thickness (x’). Transient responses of batch and continuous adsorbers containing core-shell adsorbents were predicted, assuming rectangular or Langmuir-type adsorption isotherms. In batch adsorber, the removal rate of adsorbates increased with increasing Biot number (Bi), and the decaying rate of the adsorbate concentration increased in the order of sphere > cylinder > slab. The equilibrium concentration of adsorbate in batch adsorber decreased with decreasing value of x’ due to the increased volume of active shell in the adsorbents. In continuous adsorber with suspended adsorbents, the adsorbate concentration was affected by feed rate and initial concentration of adsorbate, and the breakthrough curve was saturated more slowly by cascade connection. In fixed bed adsorber, the adsorbate concentration increased more rapidly with increasing x’ for insufficient active volume for adsorption. The breakthrough curve was also affected by Bi and Peclet number (Pe) as well as adsorbent shape, implying that external resistance and axial dispersion, as well as interfacial area, are an important factor for adsorber design. Estimations of effective diffusivity and Pe were possible from experimental data of organic dye by macroporous silica microspheres or micro-fibers as adsorbents.