Pickering Emulsions Stabilized by Hybrid TiO2-pNIPAm Composites for the Photocatalytic Degradation of 4-Propylbenzoic Acid.

Pickering emulsions (PEs) have demonstrated significant potential in various fields, including catalysis, biomedical applications, and food science, with notable advancements in wastewater treatment through photocatalysis. This study explores the development and application of TiO₂-poly(N-isopropylacrylamide) (pNIPAm) composite gels as a novel framework for photocatalytic wastewater remediation. The research focuses on overcoming challenges associated with conventional nanoparticle-based photocatalytic systems, such as agglomeration and inefficient recovery of particles. By integrating TiO₂ nanoparticles into pNIPAm gels, we aimed to achieve high emulsion stability and photocatalytic efficiency while suppressing the effects of pNIPAm's volume phase transition temperature (VPTT) to facilitate effective emulsion recovery. The study involves the synthesis of TiO₂-pNIPAm composites with varying monomer-to-particle ratios, characterizing their VPTT behavior, morphology, and thermal stability. These composites were then evaluated for their emulsification properties, phase transition behavior, and photocatalytic activity in degrading 4-propylbenzoic acid, a model pollutant. The results highlight the effectiveness of the TiO₂-pNIPAm Pickering emulsions in wastewater treatment, offering improved stability and reusability compared to traditional dispersion-based systems. This work provides new insights into the design of composite materials for enhanced photocatalytic applications and demonstrates the potential of Pickering emulsions in sustainable environmental remediation.