Modification of TiO₂ with copper oxides clusters (CuO_x-TiO₂) induces visible-light absorption and enhances its activity. In this work, we investigated the CuO_x-anatase and CuO_x-rutile for the photocatalytic oxidation of gaseous NH₃ under visible light. In contrast with the widely reported results that CuO_x-anatase displays higher performance than CuO_x-rutile in photocatalytic oxidation or reduction, we surprisingly observed that CuO_x-rutile is able to oxidize NH₃ efficiently under visible light irradiation, while CuO_x-anatase shows no activity. Further characterizations showed that visible-light inclines to drive the VB electrons of rutile TiO₂ to CuO_x at the interface between rutile TiO₂ and CuO_x, while it drives the electrons of CuO_x to anatase TiO₂ at interface between anatase TiO₂ and CuO_x. DFT calculations revealed that the interaction between CuO_x and TiO₂ is markedly different in CuO_x-anatase and CuO_x-rutile, which induces the differences in the electronic distribution of interfacial Cu, O and Ti atoms, resulting in the distinct direction of charge transfer.

用氧化铜簇 (CuO _x -TiO ₂ )修饰 TiO _{2 会}诱导可见光吸收并增强其活性。在这项工作中，我们研究了 CuO _{x -}锐钛矿和 CuO _{x -}金红石在可见光下光催化氧化气态 NH ₃。与广泛报道的CuO _{x -}锐钛矿在光催化氧化或还原中表现出比CuO _{x -}金红石更高的性能相反，我们惊讶地观察到CuO _{x -}金红石能够在可见光照射下有效地氧化NH ₃，而CuO _x-锐钛矿显示无活性。进一步表征表明，可见光倾斜驱动的金红石型二氧化钛的VB电子₂对于CuO _X在之间金红石型二氧化钛的界面₂和CuO _X，而它的驱动器的CuO的电子_X锐钛矿二氧化钛₂在界面锐钛矿二氧化钛之间₂和CuO的_X。DFT计算表明，氧化铜之间的相互作用_X和TiO ₂是以CuO明显不同的_X -anatase和CuO _X-金红石，它引起界面Cu、O和Ti原子电子分布的差异，导致电荷转移的不同方向。