Constructing anatase TiO/Amorphous NbO heterostructures to enhance photocatalytic degradation of acetaminophen and nitrogen oxide.

TiO nanostructures have been one of the most explored metal oxides photocatalysts to apply for environmental remediation. However, its wide band gap results in the underutilization of sunlight for degradation of pollutants. In order to overcome this handicap, the synthesis of TiO-based composite has brought extraordinary materials. In this study, we design and prepare TiO/NbO heterostructures with different molar ratios by using peroxotitanium and peroxoniobium complex as precursors in aqueous solution. The TiO exists in the form of anatase while NbO is amorphous in the composite, leading to a special crystalline TiO/amorphous NbO heterostructures. In particular, Nb element is also doped and Ti ions are formed in the TiO lattice, leading to a reduced band gap. The unique TiO/0.25NbO (Ti:Nb = 2:1) heterostructures can effectively suppress the recombination of photogenerated electrons and holes, and facilitate the charge transfer, resulting in the optimum photocatalytic performance. The nitrogen oxide removal efficiency by TiO/0.25NbO is 77.23% in visible light, which is 3.8-folds and 7.0-folds higher than pure TiO and NbO Photocatalytic degradation of acetaminophen by TiO/0.25NbO is 90.6% in visible light, which is approximately 2.5-folds higher than pure TiO and NbO.