Interfacial engineering over tungsten oxide by constructing Z-scheme interatomic junction for efficient photocatalytic tetrachlorophenol degradation.

Schematic illustration of the energy band positions of h-WO 3 and o-WO 3 ·H 2 O showing the internal electric field from h-WO 3 (+) to o-WO 3 ·H 2 O (−), and the possible Z-scheme carriers transfer mechanism for 4CP degradation. [Display omitted] • Co-grown preparation method is effective in building chemical bonds at heterophase junctions. • 26 h/o-WO 3 has less-defective and low lattice mismatching interface. • The -W-O-W- "bridge" acts as electron transfer channel for building internal electric field at h-WO 3 /o-WO 3 ·H 2 O interface. • Up to 2.5 e electrons migrate from h-WO 3 to o-WO 3 ·H 2 O to form a strong internal electric field at their interface. Surface defect states and lattice mismatch are two most crucial problems to be resolved in hetero-interface photocatalysts design for achieving highly efficient photocatalytic performance. Co-grown interfacial regulation strategy has been pointed out in this work as a feasible way for fabrication interatomic junction with less-defective and abrupt interface. By simply hydrothermal step, the selected model 26 h/o-WO 3 hetero-phase junction with outstanding interface structure is prepared. Two constituents of 26 h/o-WO 3 , h-WO 3 and o-WO 3 ·H 2 O connect to each other though consecutive -W-O-W- chemical bonds with 0.058 lattice mismatching at their interface. This novel 26 h/o-WO 3 interatomic junction exhibits superior photocatalytic activity for the degradation of Tetrachlorophenol as compared with its comparative 26 h/o-WO 3 (L) prepared by loading method, as well as pristine h-WO 3 and o-WO 3 ·H 2 O. Investigations on the charge dynamics and carriers separation mechanism demonstrate that the superior photocatalytic activity mainly results from the synergistic effects of ultrafast carrier transport, and great driving force from internal electric field formed though consecutive chemical bonds at interface. This work provides a facile way to develop interatomic junction showing great internal electric field for boosting photocatalytic activities. [ABSTRACT FROM AUTHOR]