3D nanostructured N-doped TiO2 photocatalysts with enhanced visible absorption. Issue 20 (16th May 2018) - Cho, Sumin
Abstract : Our work introduces 3D nanostructured N-doped TiO2 with enhanced visible absorption for enhanced visible photocatalysis via PnP and ALD techniques. Abstract : Considering the environmental issues, it is essential to develop highly efficient and recyclable photocatalysts in purification systems. Conventional TiO2 nanoparticles have strong intrinsic oxidizing power and high surface area, but are difficult to collect after use and rarely absorb visible light, resulting in low photocatalytic efficiency under sunlight. Here we develop a new type of highly efficient and recyclable photocatalyst made of a three-dimensional (3D) nanostructured N-doped TiO2 monolith with enhanced visible light absorption. To prepare the sample, an ultrathin TiN layer (∼10 nm) was conformally coated using atomic layer deposition (ALD) on 3D nanostructured TiO2 . Subsequent thermal annealing at low temperature (550 °C) converted TiN to anatase phase N-doped TiO2 . The resulting 3D N-doped TiO2 showed ∼33% enhanced photocatalytic performance compared to pure 3D TiO2 of equivalent thickness under sunlight due to the reduced bandgap, from 3.2 eV to 2.75 eV through N-doping. The 3D N-doped TiO2 monolith could be easily collected and reused at least 5 times without any degradation in photocatalytic performance.