Mixed TiO2-SiO2 thin layers exhibiting an ordered mesoporosity are prepared for future photocatalytic applications. They are synthesized from a nanocrystalline anatase hydrosol, tetraethylorthosilicate as silica source and triblock copolymers as mesostructuring agent. It has been previously demonstrated that the preparation of mesoporous anatase-based thin layers is possible at low temperature (423 K) by using the photodegradation of the templating mesophases. Layer consolidation is required before a possible application. Polymerized silica can be used as inorganic binder to improve the stability of such low-temperature layers. The effect of addition of silica on the crystalline structure, on the mesostructure, on the porosity and on the photocatalytic activity is here presented and discussed. (c) 2005 Elsevier B.V. All rights reserved.