National Engineering Research Center for Nanotechnology, Shanghai 200241, PR China.
Nanoscale. 2013 Jan 21;5(2):588-93. doi: 10.1039/c2nr33109h. Epub 2012 Dec 3.
Shell@core-nanostructured TiO(2)@ZnO n-p-n heterojunction nanorods with diameter of 30 nm were successfully fabricated via a hydrothermal method. The photodegradation rate of the TiO(2)@ZnO n-p-n nanorods evaluated by photodegrading methyl orange has been demonstrated to increase three times compared to that of wurtzite hexagonal ZnO. Anatase TiO(2) and Ti(2)O(3) grow along ZnO crystal lattices, which forms p-type Zn(2+) doped Ti(2)O(3) in the interface of TiO(2)/ZnO and therefore numerous n-p-n heterojunctions owing to the substitution of Ti(3+) by Zn(2+). Under the drive of inner electric field, the photogenerated electrons are both injected to the conduction band of Zn(2+) doped Ti(2)O(3) from conduction bands of ZnO and TiO(2), which efficiently enhances the separation of photogenerated electron-hole pairs and accelerates the transport of charges. The results suggest that TiO(2)@ZnO n-p-n heterojunction nanorods are very promising for enhancing the photocatalytic activity of photocatalysts.
壳@纳米结构二氧化钛@氧化锌 n-p-n 异质结纳米棒，直径 30nm，通过水热法成功制备。通过光降解甲基橙评估的 TiO(2)@ZnO n-p-n 纳米棒的光降解率已经证明比纤锌矿六方 ZnO 增加了三倍。锐钛矿 TiO(2)和 Ti(2)O(3)沿着 ZnO 晶格生长，这在 TiO(2)/ZnO 的界面形成 p 型 Zn(2+)掺杂的 Ti(2)O(3)，因此由于 Ti(3+)被 Zn(2+)取代，形成了许多 n-p-n 异质结。在内部电场的驱动下，光生电子从 ZnO 和 TiO(2)的导带注入到 Zn(2+)掺杂的 Ti(2)O(3)的导带中，这有效地增强了光生电子空穴对的分离，并加速了电荷的传输。结果表明，TiO(2)@ZnO n-p-n 异质结纳米棒非常有希望提高光催化剂的光催化活性。
