Ultrathin Na2Ti9O19 heterostructural nanosheets modified with TiO2 nanoparticles for enhanced photocatalysis

TiO2 nanoparticles (TNPs) modified ultrathin Na2Ti9O19 heterostructural nanosheets arrays are successfully synthesized by novel two-step hydrothermal growth method. Our investigation of their photocatalytic degradation methyl orange (MO) under simulated sunlight irradiation suggests that TiO2@Na2Ti9O19 nanosheets possess dramatically enhanced photocatalytic activity, and their degradation efficiency is nearly 2.4 times higher than that of the pure Na2Ti9O19 nanosheets arrays for 2 h. After 4 cycles, their photocatalytic activities are kept almost unchanged, showing perfect reusability and superior stability, which would be attributed to their uniquely oriented heterostructural nanosheet arrays, matched energy level structure, and intimate interface contact.