Titanium Dioxide (TiO2) and Photocatalysis: A Detailed Overview of the Synthesis, Applications, Challenges, Advances and Prospects for Sustainable Development

Emerging contaminants in aquatic ecosystems demand advanced remediation strategies, with semiconductor photocatalysis standing out as a transformative technology. This review examines material design innovations, focusing on sol-gel, hydrothermal, and ultrasonic synthesis methods that enable precise control over structural properties critical for photocatalytic efficiency. Doping with metals/non-metals and heterostructure engineering are highlighted for adjusting bandgap energy to enhance visible-light absorption. Advanced characterization techniques, including XRD and electron microscopy, reveal correlations between material architecture and performance. Applications encompass solar-driven degradation of pharmaceuticals, antimicrobial surface coatings, and hybrid systems combining photocatalysis with membrane filtration or ozonation. Scalability challenges are addressed through immobilized catalysts and reactor design innovations. Interdisciplinary approaches integrating AI optimization and agro-industrial waste valorization underscore sustainable synthesis pathways. Functionalized materials demonstrate dual utility in environmental and biomedical contexts, while solar hydrogen production aligns with clean energy objectives. Persistent barriers include energy efficiency optimization and long-term catalyst stability. Future research emphasizes adaptive material architectures, circular economy integration, and synergistic coupling with conventional treatment processes. By bridging lab-scale advances with industrial scalability, photocatalysis emerges as a versatile solution for water purification and sustainable resource management, offering a roadmap for addressing complex environmental challenges.