ZnO/Cu_2O异质结纳米阵列制备及光催化性能

利用湿化学法在FTO玻璃基底上制备了高度规整的ZnO纳米棒阵列(ZnO NRAs),以此为衬底,采用磁控溅射法在ZnO NRAs表面沉积Cu_2O薄膜。分别用X射线衍射仪、X射线光电子能谱、扫描电镜、光致光谱、紫外可见分光光度计和电化学工作站对样品的物相、形貌、吸收光谱、光电性能进行了表征,用甲基橙(MO)模拟有机物废水研究复合材料的光催化性能。结果表明:ZnO纳米棒为六方纤锌矿结构,其直径约为80~100 nm,长约2~3μm,棒间距约100~120 nm。立方晶系的Cu_2O颗粒直径约为100~300 nm,形成致密膜层并紧密覆盖在ZnO NRAs表面上,构成ZnO/Cu_2O异质结纳米阵列(ZnO/Cu_2O HNRAs)结构。与纯ZnO NRAs和Cu_2O相比,ZnO/Cu_2O HNRAs在可见光范围内的吸收显著增强,吸收波长向可见光方向偏移。ZnO/Cu_2O HNRAs的载流子传递界面的电荷转移速度快,有效促进了光生电子和空穴的分离。在紫外-可见光照射65 min后,ZnO/Cu_2O HNRAs的降解效率为94%,分别是纯ZnO NRAs和Cu_2O的18倍和1.7倍。

Preparation and Photocatalytic Property of ZnO/Cu2 O Heterostructured Nanorod Arrays

ZnO nanorod arrays ( ZnO NRAs ) on FTO-glass substrates were prepared by chemical method, then Cu2O film was deposited on ZnO NRAs surface by using magnetron sputtering method. The crystal phase, morphology, UV-Vis absorbance spectra and photoelectric property were charac-terized by X-ray diffraction, X-ray photoelectron spectroscope, scanning electron microscopy, photo-luminescence spectroscopy, UV-Vis spectrophotometer and electrochemical workstation, respective-ly. The photocatalytic activity was evaluated by the photocatalytic degradation of methyl orange ( MO) under UV-Vis light irradiation. The results show that ZnO NRAs are wurtzite structure phase with diameter of 80-100 nm, length of 2-3μm, and rod interval distance of 100-120 nm. Cu2 O particles are the cubic phase with grain diameter of 100-300 nm and form a dense membrane layer on ZnO NRAs, which constitutes ZnO/Cu2 O heterojunction nanorod arrays ( ZnO/Cu2 O HNRAs ) structure. Compared with pure ZnO NRAs and Cu2 O film, the absorption intensity in the visible region of ZnO/Cu2 O HNRAs is significantly enhanced and the absorption wavelength redshifts. The charge transfer speed on the carrier transmission interface of ZnO/Cu2 O HNRAs is faster, contribu-ting to the separation of photoelectrons from hole. Irradiated under UV-Vis light for 65 min, the MO degradation efficiency of ZnO/Cu2 O HNRAs is 94%, 18 times than that of pure ZnO NRAs and 1. 7 times than that of pure Cu2 O film.