Yonsei Institute of Convergence Technology, Yonsei University, Yeonsu-gu, Incheon 21983, Republic of Korea.
School of Integrated Technology, Yonsei University, Yeonsu-gu, Incheon 21983, Republic of Korea.
Sci Rep. 2016 Sep 16;6:33525. doi: 10.1038/srep33525.
Lightweight, simple and flexible self-powered photodetectors are urgently required for the development and application of advanced optical systems for the future of wearable electronic technology. Here, using a low-temperature reduction process, we report a chemical approach for producing freestanding monolithic reduced graphene oxide papers with different gradients of the carbon/oxygen concentration ratio. We also demonstrate a novel type of freestanding monolithic reduced graphene oxide self-powered photodetector based on a symmetrical metal-semiconductor-metal structure. Upon illumination by a 633-nm continuous wave laser, the lateral photovoltage is observed to vary linfearly with the laser position between two electrodes on the reduced graphene oxide surface. This result may suggest that the lateral photovoltaic effect in the reduced graphene oxide film originates from the built-in electric field by the combination of both the photothermal electric effect and the gradient of the oxygen-to-carbon composition. These results represent substantial progress toward novel, chemically synthesized graphene-based photosensors and suggest one-step integration of graphene-based optoelectronics in the future.
对于未来可穿戴电子技术的先进光学系统的发展和应用，急需轻巧、简单且灵活的自供电光电探测器。在这里，我们使用低温还原工艺，报告了一种化学方法，用于生产具有不同碳/氧浓度比梯度的独立整体还原氧化石墨烯纸。我们还展示了一种基于对称金属-半导体-金属结构的新型独立整体还原氧化石墨烯自供电光电探测器。在对 633nm 连续波激光进行照射时，观察到横向光电压随激光在还原氧化石墨烯表面两个电极之间的位置线性变化。这一结果表明，在还原氧化石墨烯薄膜中的横向光伏效应源于光热电场和氧碳组成梯度的组合所产生的内置电场。这些结果代表了在新型化学合成的基于石墨烯的光传感器方面取得了重大进展，并为未来基于石墨烯的光电集成提供了一种可能。
