Cu-Cu2O-TiO2 nanojunction systems with an unusual electron-hole transportation pathway and enhanced photocatalytic properties.

Multicomponent Cu-Cu2O-TiO2 nanojunction systems were successfully synthesized by a mild chemical process, and their structure and composition were thoroughly analyzed by X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy, and X-ray photoelectron spectroscopy. The as-prepared Cu-Cu2O-TiO2 (3 and 9 h) nanojunctions demonstrated higher photocatalytic activities under UV/Vis light irradiation in the process of the degradation of organic compounds than those of the Cu-Cu2O, Cu-TiO2, and Cu2O-TiO2 starting materials. Moreover, time-resolved photoluminescence spectra demonstrated that the quenching times of electrons and holes in Cu-Cu2O-TiO2 (3 h) is higher than that of Cu-Cu2O-TiO2 (9 h); this leads to a better photocatalytic performance of Cu-Cu2O-TiO2 (3 h). The improvement in photodegradation activity and electron-hole separation of Cu-Cu2O-TiO2 (3 h) can be ascribed to the rational coupling of components and dimensional control. Meanwhile, an unusual electron-hole transmission pathway for photocatalytic reactions over Cu-Cu2O-TiO2 nanojunctions was also identified.

From titanium oxydifluoride (TiOF2) to titania (TiO2): phase transition and non-metal doping with enhanced photocatalytic hydrogen (H2) evolution properties.

Single-crystalline TiOF(2) crystals with cubical morphology were prepared via a facile solvothermal method and their transformation to anatase TiO(2) under different calcination conditions such as pure argon, moist argon and pure hydrogen sulfide (H(2)S) was explored by using XRD/Raman/UV-Vis/SEM/TEM/SAED. The non-metal sulfur doping was successfully fulfilled and the doped TiO(2) microcubes showed the best photocatalytic H(2) evolution property.

Synthesis of micro-sized titanium dioxide nanosheets wholly exposed with high-energy {001} and {100} facets.

A new synthetic strategy was developed to prepare large-sized well-defined anatase TiO(2) nanosheets wholly dominated with thermodynamically unfavorable high-reactive {001} and {100} facets, which has a percentage of 98.7% and 1.3%, respectively. The as-prepared anatase TiO(2) nanosheets show a well-faceted morphology and have a large size in length (ca. 4.14 µm). The formation mechanism of the anatase TiO(2) nanosheets was also analyzed and investigated.