Zinc oxide (ZnO) has been widely investigated as an important ultraviolet (UV) sensing material in view of its wide band gap (~3.4 eV). However, the fabrication of continuous thin films of ZnO generally requires complex, time-consuming, and expensive processes, such as sputtering and atomic layer deposition. Herein, we demonstrate a bilayer film consisting of a conducting polymer and ZnO nanoparticles sequentially deposited using a simple, rapid, and inexpensive two-step spin-coating process. In this approach, it is not necessary to have a continuous ZnO nanoparticle film as the active layer, because the conducting polymer deposited under the ZnO nanoparticles acts as a conductive and continuous supporting layer for the particles. Poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT: PSS) is used as the auxiliary layer to promote the efficient transport of photo-carriers generated from ZnO nanoparticles under UV light. As a result, under UV light (365 nm), photocurrents obtained from a ZnO/PEDOT: PSS bilayer film are significantly higher (∼20 times) than that from a ZnO layer for a given voltage bias. The photoelectric performance can be further tuned by controlling the speed of spin-coating in the deposition of ZnO nanoparticles. The stability and photo response (rise and decay time) of the ZnO/PEDOT: PSS bilayer film under the repeated on-off condition are also reported.

中文翻译：

---

ZnO/导电聚合物双层通过顺序旋涂增强紫外线传感

鉴于其宽带隙（~3.4 eV），氧化锌（ZnO）作为一种重要的紫外线（UV）传感材料已被广泛研究。然而，制备连续的 ZnO 薄膜通常需要复杂、耗时且昂贵的工艺，例如溅射和原子层沉积。在此，我们展示了一种双层薄膜，该薄膜由导电聚合物和 ZnO 纳米颗粒组成，使用简单、快速且廉价的两步旋涂工艺依次沉积。在这种方法中，没有必要将连续的 ZnO 纳米粒子薄膜作为活性层，因为沉积在 ZnO 纳米粒子下方的导电聚合物充当粒子的导电和连续支撑层。聚（3,4-亚乙基二氧噻吩）：聚苯乙烯磺酸盐（PEDOT：PSS) 用作辅助层，以促进在紫外光下由 ZnO 纳米粒子产生的光载流子的有效传输。因此，在紫外光（365 nm）下，对于给定的偏压，从 ZnO/PEDOT: PSS 双层膜获得的光电流明显高于（~20 倍）来自 ZnO 层的光电流。通过控制 ZnO 纳米颗粒沉积中的旋涂速度，可以进一步调节光电性能。还报告了重复开关条件下 ZnO/PEDOT: PSS 双层膜的稳定性和光响应（上升和衰减时间）。对于给定的偏压，PSS 双层膜明显高于 ZnO 层（约 20 倍）。通过控制 ZnO 纳米颗粒沉积中的旋涂速度，可以进一步调节光电性能。还报告了重复开关条件下 ZnO/PEDOT: PSS 双层膜的稳定性和光响应（上升和衰减时间）。对于给定的偏压，PSS 双层膜明显高于 ZnO 层（约 20 倍）。通过控制 ZnO 纳米颗粒沉积中的旋涂速度，可以进一步调节光电性能。还报告了重复开关条件下 ZnO/PEDOT: PSS 双层膜的稳定性和光响应（上升和衰减时间）。