Oxygen vacancy（VO） plays a vital role in semiconductor photocatalysis. Rutile TiO2 nanomaterials with controllable contents of VO（0–2.18%） are fabricated via an insitu solid-state chemical reduction strategy, wit...Oxygen vacancy（VO） plays a vital role in semiconductor photocatalysis. Rutile TiO2 nanomaterials with controllable contents of VO（0–2.18%） are fabricated via an insitu solid-state chemical reduction strategy, with color from white to black. The bandgap of the resultant rutile TiO2 is reduced from 3.0 to 2.56 e V, indicating the enhanced visible light absorption. The resultant rutile TiO2 with optimal contents of VO（2.07%） exhibits a high solar-driven photocatalytic hydrogen production rate of 734 μmol h-1, which is about four times as high as that of the pristine one（185 μmol h-1）. The presence of VOelevates the apparent Fermi level of rutile TiO2 and promotes the efficient electronhole separation obviously, which favor the escape of photogenerated electrons and prolong the life-time（7.6×103 ns） of photogenerated charge carriers, confirmed by scanning Kelvin probe microscopy, surface photovoltage spectroscopy and transient-state fluorescence. VO-mediated efficient photogenerated electron-hole separation strategy may provide new insight for fabricating other high-performance semiconductor oxide photocatalysts.展开更多
基金supported by the Key Program Projects of the National Natural Science Foundation of China (21631004)the National Natural Science Foundation of China (51672073)
文摘Oxygen vacancy（VO） plays a vital role in semiconductor photocatalysis. Rutile TiO2 nanomaterials with controllable contents of VO（0–2.18%） are fabricated via an insitu solid-state chemical reduction strategy, with color from white to black. The bandgap of the resultant rutile TiO2 is reduced from 3.0 to 2.56 e V, indicating the enhanced visible light absorption. The resultant rutile TiO2 with optimal contents of VO（2.07%） exhibits a high solar-driven photocatalytic hydrogen production rate of 734 μmol h-1, which is about four times as high as that of the pristine one（185 μmol h-1）. The presence of VOelevates the apparent Fermi level of rutile TiO2 and promotes the efficient electronhole separation obviously, which favor the escape of photogenerated electrons and prolong the life-time（7.6×103 ns） of photogenerated charge carriers, confirmed by scanning Kelvin probe microscopy, surface photovoltage spectroscopy and transient-state fluorescence. VO-mediated efficient photogenerated electron-hole separation strategy may provide new insight for fabricating other high-performance semiconductor oxide photocatalysts.
