Photocatalytic paper from colloidal TiO2 -: fact or fantasy

Photocatalytic paper encompasses a range of materials based on paper and nonwoven fabrics which performs a function based on the light-activated catalytic activity of colloidal TiO2. The literature describing photocatalytic paper is surveyed, including mechanisms, applications, limitations and future opportunities. The technology is in its infancy with less than 10 patents and as many scientific publications appearing over the last decade. The main applications described are the destruction of organic molecules (mineralization) and photo-disinfection (sterilization). These disclosures build upon a much larger literature describing photochemical properties of TiO2 both supported on non-cellulose substrates or simply as suspended particles in water or air. Current photocatalytic paper developments include methods to fix TiO2 to cellulose substrates to minimize photochemical damage to the paper. Another theme is the use of multiple approaches, such as zeolites, for enhanced mineralization, and metals, such as silver and copper, for enhanced photocatalytic disinfection. 2006 Elsevier B.V. All rights reserved.