Tailored Synthesis of Pt-Nanoparticle-Modified Mesoporous TiO2 Popcorn-Like Nanostructures for Photocatalytic Applications

摘要

Designing green and efficient photocatalysts for pollutant degradation is of great significance, where the photogenerated charge separation plays an important role in improving the photocatalytic efficiency. A three-dimensional popcorn-like TiO2 mesoporous sphere with tunable Pt contents has been successfully synthesized by a combination of hydrothermal process and chemical reduction. The resultant Pt/TiO2 mesoporous spheres exhibit a suppressed charge recombination due to the synergic effect of TiO2 and Pt. To be specific, the Pt nanoparticle on the TiO2 facilitates the collection and transfer of the photogenerated electrons originated from the mesoporous TiO2. Density functional theory (DFT) calculated results further confirm the faster carries separation in Pt/TiO2. Meanwhile, the specific three-dimensional structure endows Pt/TiO2 spheres with enhanced light scattering ability, a high surface area, and porous structure. As a consequence, the novel Pt/TiO2 mesoporous spheres present multiple fold enhancement on the RhB photodegradation efficiency compared with that of neat TiO2, in which 1.0 Pt/TiO2 presents the highest photocatalytic activity. This work proposes a new perspective of green and efficient photocatalysts.