Negative oxygen ion (NOI) production by enhanced photocatalytic TiO 2 /GO composites anchored on wooden substrates

Titanium dioxide (TiO 2 )/graphene oxide (GO)-treated wood was fabricated through a one-step hydrothermal-vacuum dipping technique, in which silica sol serves as a dispersant and linker owing to its good stability and high surface area, while the visible light activates TiO 2 /GO and negative oxygen ions (NOI) arise. This approach exhibits a super dye adsorption capacity and enhanced photocatalytic efficiency. In focus was the effect of the three-dimensional (3D) GO dopant on the NOI production, which was very high in this system. Namely, the concentration of NOI is up to 1710 ions cm −3 after 60 min visible light irradiation. Moreover, recycling experiments show that the properties of a TiO 2 /GO-wood system are stable. The TiO 2 /GO-treated wood is a healthy, environmentally friendly material which is promising for indoor decoration.