Low-temperature synthesis of water-dispersible anatase titanium dioxide nanoparticles for photocatalysis

[Display omitted] ► Water-dispersible TiO2 nanoparticles were synthesized at 80°C without surfactants. ► TiO2 nanoparticles were stabilized by electrostatic. ► TiO2 nanoparticles possess excellent quinoline degradation activity and recycle stability. ► Enhanced activity is due to large specific surface area and easy electron-hole transportation. Water-dispersible anatase TiO2 nanoparticles were synthesized at a low temperature (80°C) without using surfactants via the mechanism of electrostatic stabilization. The water-dispersible TiO2 nanoparticles solution was stable and no precipitation occurred after 3months. Photocatalytic evaluation demonstrated that the as-synthesized TiO2 nanoparticles possess excellent quinoline degradation performance (a 2.33×10−2min−1 apparent reaction rate constant comparing to 1.22×10−2min−1 for P25) and recycle stability (the photocatalytic activity remained 96.6% of the initial activity after four cycles of repetitive uses). These could be attributed to the small size and good water-dispersibility of the as-synthesized TiO2 nanoparticles that led to large specific surface area and easy photogenerated electron–hole transportation.