Silica Decorated TiO^sub 2^ for Virus Inactivation in Drinking Water - Simple Synthesis Method and Mechanisms of Enhanced Inactivation Kinetics

A new method of modifying ... photocatalysts with ... is developed in which ... nanoparticles are simply mixed with ... in water under ambient conditions. This method does not require the use of toxic solvents or significant energy input. Although the ... modification slightly reduces hydroxyl free radical production, the composite ... nanomaterials have markedly higher photocatalytic inactivation rates for a common surrogate virus, bacteriophage MS2 (up to 270% compared to the unmodified ...), due to the greatly improved adsorptive density and dark inactivation of MS2. The Langmuir isotherm describes the adsorption data well and shows that the ... modified with 5% ... has a maximum adsorption density qmax 37 times that of the unmodified ... The Langmuir-Hinshelwood model fits the photocatalytic inactivation kinetic data well. The ... material produces a greater maximum initial inactivation rate yet a lower intrinsic surface reaction rate constant, consistent with the reduced hydroxyl radical production and enhanced adsorption. These results suggest that modifying photocatalyst surface to increase contaminant adsorption is an important strategy to improve photocatalytic reaction efficiency. Simple and cheap synthesis methods such as that used in this study bring photocatalysis closer to being a viable water treatment option. (ProQuest: ... denotes formulae/symbols omitted.)