Highly Efficient Visible Light Catalysts Driven by Ti³⁺-V_O-2Ti⁴⁺-N³⁻ Defect Clusters

Local defect structures play significant roles on material properties, but they are seriously neglected in the design, synthesis, and development of highly efficient TiO₂-based visible light catalysts (VLCs). Here, we take anatase TiO₂ nanocrystals that contain (Ti³⁺, N³⁻) ions and have the complicated chemical formula of (Ti_1-x ⁴⁺Ti_x ³⁺)(O^2- _2-y-zN_y ^3-□_z) as an example, and point out that the formation of Ti³⁺-V_O-2Ti⁴⁺-N³⁻ local defect clusters is a key missing step for significantly enhancing VLC properties of host TiO₂ nanocrystals. Experimental and theoretical investigations also demonstrate the emergent behaviors of these intentionally introduced defect clusters for developing highly efficient VLCs. This research thus not only provides highly efficient visible light catalysts for various practical applications but also addresses the significance of local defect structures on modifying material properties.