TiO₂ Nanoparticles Supported on Hierarchical Meso/Macroporous SiO₂ Spheres for Photocatalytic Applications

Abstract

Supporting a photocatalyst, such as titania nanoparticles (TiO 2 NPs), is a good strategy to improve its performance since it can facilitate the photocatalyst recovery from the aqueous media and provides a high surface area for pollutant adsorption. Among the several advanced functional materials used as TiO 2 NP support, the hierarchical meso/macroporous SiO 2 spheres not only show the advantages associated to its chemical nature but also the dendritic fibrous structure provides a porous network that offers many benefits to be exploited in optical and catalytic devices. In this chapter, different synthetic approaches to design hierarchical meso/macroporous silica and the strategies to support TiO 2 NPs regarding the photocatalytic performance of these materials are shown.

Biomimetic Hierarchical Superstructures: Approaches Using Bicontinuous Microemulsions and Electrodeposition

“…This feature is highly desirable in some applications because it provides a high specific surface area and suitable interaction with external parameters, such as radiation. Figure 4B shows SiO 2 spheres with hierarchical porosity decorated with TiO 2 nanoparticles (TiO 2 NPs) for photocatalytic applications (Fuentes et al, 2019). The SiO 2 corrugated spheres obtained as described previously were decorated by depositing titanium isopropoxide in isopropanol and treated under hydrothermal conditions to achieve the crystallization of TiO 2 NPs in the anatase phase with a mean particle size of approximately 10 nm.…”

“…Hierarchical meso-macroporous materials have the advantage that their constituent blocks provide size and shape selectivity, which has led to several applications involving interactions with host molecules. Macropores favor the diffusion and accessibility of host molecules, while mesopores provide a high surface area to enhance adsorption (Fuentes et al, 2019).…”