One-Step Hydrothermal Synthesis of Small TiO2 Porous Nanoparticles for Efficient Degradation of Organic Dyes

: In the work, small TiO2 porous nanoparticles with an average size of 60 nm have been prepared by a simple, eco-friendly, and one-step hydrothermal method. The TiO2 products are achieved by only using tetrabutyl titanate (TBOT), tetrapropylammonium hydroxide (TPAOH), and water as the starting materials. Various techniques such as SEM, TEM, HRTEM, XRD, Raman, and BET are used to characterize the surface morphology and structural features of products. The growth parameters including reaction time, titanium source and temperature of thermal treatment are systematically investigated. In the synthesis, TPAOH plays a decisive role as structure-directing agent for the formation of desirable TiO2 nanostructure. The photocatalytic tests manifest that the TiO2 nanoparticles annealed at 450 °C shows an outstanding photocatalytic activity for degradation of methyl orange (MO) and rhodamine B (RhB), which is comparable to Degussa P25. The superior performance may mainly come from the contributions of their small particle size and unique nanostructure.