Thermoreversible Engineering of Sol-gel Photocatalytic Coatings for Next-Generation Air Purification

Next-generation environmental technologies require materials that are not only efficient, but adaptive, durable, and intrinsically linked to process control. This work advances photocatalytic sol-gel systems by treating their temporal evolution as a design variable rather than a constraint. Through controlled thermal modulation and microrheological interrogation, aqueous TiO2 and SiO2 sols are engineered as dynamic precursor platforms, where viscoelastic transitions control film formation, interfacial adhesion, and active surface development. A key innovation lies in the deliberate use of thermoreversibility to stabilize and reactivate sol structures, enabling long-life formulations that retain functionality over extended periods. This approach allows the reproducible fabrication of thick layered, high-loaded coatings optimized for gas-phase photocatalytic degradation of volatile organic compounds, including formaldehyde and acetaldehyde under realistic flow conditions. By shifting from static material optimization to dynamic structure-process-function engineering, this research establishes a framework for efficient photocatalytic systems capable of consistent performance in operational environments. Such strategies are critical for the development of scalable, energy-efficient air purification technologies and represent a decisive step toward next-generation materials that actively respond to evolving environmental demands.