TiO2-Intercalated Graphene Oxides with Highly Efficient Photocatalytic Degradation for Methylene Blue

Abstract EN

The low photocatalytic decomposition activity of TiO2 toward industrial pollutants at room temperature is one of the main obstacles for its practical application.

TiO2-intercalated graphene oxide (GO) composites were prepared by in situ hydrolysis of butyl titanate in a GO aqueous solution, followed by hydrothermal reaction to improve their photoelectron separation efficiency.

The in situ generated TiO2 nanocrystals could grow and adhere to the GO walls, thereby greatly improving the contact area and binding strength among them and resulting in low photoelectron transfer resistance.

The photocatalytic activities of the as-prepared catalyst were evaluated via photodegradation of methylene blue (MB).

The TiO2-intercalated GOs displayed much higher catalytic activity than GO, TiO2, and TiO2-adsorbed GOs.

The degradation efficiency of MB by TiO2-intercalated GOs increased with increasing bath ratio of TiO2-intercalated GOs to MB solution, but it decreased with increasing initial concentration of MB.

Degradation of MB by UV light was much faster than by simulated sunlight.

The degradation time by sunlight was only 5% of degradation time by UV light.

Cyclic catalytic experiments indicated that TiO2-intercalated GO maintained 99.97% degradation activity after repeated degradation (five times), thereby indicating the good decomposition durability.