Ouyang Weixin, Teng Feng, Jiang Mingming, Fang Xiaosheng
Department of Materials Science, Fudan University, Shanghai, 200433, P. R. China.
State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, P. R. China.
Small. 2017 Oct;13(39). doi: 10.1002/smll.201702177. Epub 2017 Aug 22.
A novel CdMoO -ZnO composite film is prepared by spin-coating CdMoO microplates on ZnO film and is constructed as a heterojunction photodetector (PD). With an optimized loading amount of CdMoO microplates, this composite film PD achieves a ≈18-fold higher responsivity than pure ZnO film PD at 5 V bias under 350 nm (0.15 mW cm ) UV light illumination, and its decay time shortens to half of the original value. Furthermore, Au nanoparticles are then deposited to modify the CdMoO -ZnO composite film, and the as-constructed photodetector with an optimized deposition time of Au nanoparticles yields an approximately two-fold higher photocurrent under the same condition, and the decay time reduces by half. The introduced CdMoO microplates form type-II heterojunctions with ZnO film and improve the photoelectric performance. The hot electrons from Au nanoparticles are injected into the CdMoO -ZnO composite film, leading to the increased photocurrent. When the light is off, the Schottky barriers formed between Au nanoparticles and CdMoO -ZnO composite film block the carrier transportation and accelerate the decay process of current. The study on Au-nanoparticle-modified CdMoO -ZnO composite film provides a facile method to construct ZnO film based PD with novel structure and high photoelectric performance.
通过在ZnO薄膜上旋涂CdMoO微板制备了一种新型的CdMoO -ZnO复合薄膜，并将其构建为异质结光电探测器（PD）。在优化CdMoO微板的负载量后，这种复合薄膜光电探测器在350 nm（0.15 mW cm ）紫外光照射下，5 V偏压下的响应度比纯ZnO薄膜光电探测器高约18倍，其衰减时间缩短至原来的一半。此外，随后沉积金纳米颗粒以修饰CdMoO -ZnO复合薄膜，构建的具有优化金纳米颗粒沉积时间的光电探测器在相同条件下产生的光电流大约高出两倍，并且衰减时间减少一半。引入的CdMoO微板与ZnO薄膜形成II型异质结并改善了光电性能。来自金纳米颗粒的热电子注入到CdMoO -ZnO复合薄膜中，导致光电流增加。当光关闭时，在金纳米颗粒与CdMoO -ZnO复合薄膜之间形成的肖特基势垒阻碍了载流子传输并加速了电流的衰减过程。对金纳米颗粒修饰的CdMoO -ZnO复合薄膜的研究提供了一种构建具有新颖结构和高光电性能的基于ZnO薄膜的光电探测器的简便方法。
