A Buoyant, Microstructured Polymer Substrate for Photocatalytic Degradation Applications

Abstract

Microbubble fabrication of poly(dimethylsiloxane) (PDMS) beads with incorporated TiO2 provides a low-density, microstructured photocatalyst that is buoyant in water. This approach surmounts many of the challenges traditionally encountered in the generation of buoyant photocatalysts, an area which is critical for the implementation of widespread environmental cleaning of organic pollutants in water resources. Because the incorporation into the polymer bead surface is done at low temperatures, the crystal structure of TiO2 is unaltered, ensuring high-quality photocatalytic activity, while PDMS is well-established as biocompatible, temperature stable, and simple to produce. The photocatalyst is shown to degrade methylene blue faster than other buoyant, TiO2-based photocatalysts, and only an order of magnitude less than direct suspension of an equivalent amount of photocatalyst in solution, even though the photocatalyst is only present at the surface of the solution. The reusability of the TiO2/PDMS beads is also strong, showing no depreciation in photocatalytic activity after five consecutive degradation trials.

Synthesis of Polystyrene@TiO2 Core–Shell Particles and Their Photocatalytic Activity for the Decomposition of Methylene Blue

“…In general, TiO 2 particles with a small particle size can efficiently act as a photocatalyst; however, these tend particles with a small particle size can efficiently act as a photocatalyst; however, these tend to agglomerate due to their high energy and reduce the number of available active sites [19]. To solve this problem, TiO2 particles have been immobilized on polymer substrates such as polymers, including polyethlene [20,21] and poly (dimethylsiloxane) beads, [22] and so on [23]. Moreover, it is difficult to obtain TiO2 particles with uniform size due to the fast sol-gel reaction rates exhibited by Ti precursors [24,25].…”

Catalysts for Oxidative Destruction of Volatile Organic Compounds

“…An article in this Special Issue focuses on this application. Bertram and Nee investigated the fabrication of polydimethylsiloxan beads, which incorporated TiO 2 and was made using a microbubble technique [7]. The approach produced an effective microstructured low-density photocatalyst that was buoyant in water.…”