Multifunctional Two-dimensional Glassy Graphene Devices For Vis-nir Photodetection And Volatile Organic Compound Sensing

Abstract

Multifunctional devices are of great interest for integration and miniaturization on the same platform, but simple addition of functionalities would lead to excessively large devices. Here, the photodetection and chemical sensing device is developed based on two-dimensional (2D) glassy-graphene that meets similar property requirements for the two functionalities. An appropriate bandgap arising from the distorted lattice structure enables glassy graphene to exhibit comparable or even improved photodetection and chemical sensing capability, compared with pristine graphene. Due to strong interactions between glassy graphene and the ambient atmosphere, the devices are less sensitive to photoinduced desorption than the ones based on graphene. Consequently, the few-layer glassy graphene device delivers positive photoresponse, with a responsivity of 0.22 A W−1 and specific detectivity reaching ~1010 Jones under 405 nm illumination. Moreover, the intrinsic defects and strain in glassy graphene can enhance the adsorption of analytes, leading to high chemical sensing performance. Specifically, the extracted signal-to-noise-ratio of the glassy graphene device for detecting acetone is 48, representing more than 50% improvement over the device based on graphene. Additionally, bias-voltage- and thickness-dependent volatile organic compound (VOC) sensing features are identified, indicating the few-layer glassy graphene is more sensitive. This study successfully demonstrates the potential of glassy graphene for integrated photodetection and chemical sensing, providing a promising solution for multifunctional applications further beyond.

本文设计了基于二维玻璃态石墨烯的多功能器件. 与本征石墨烯相比, 扭曲的晶格结构打开了玻璃态石墨烯的带隙, 表现出与石墨烯类似甚至更优异的光电探测与化学传感性能. 由于玻璃态石墨烯与空气中的小分子间较强的相互作用, 该器件受到光致脱附的影响更小, 呈现出正的光响应. 在405 nm的激光照射下, 器件的响应率为0.22 A W−1, 探测率为~1010 Jones. 此外, 玻璃态石墨烯中的固有缺陷和应变可增强分析物的吸附, 获得良好的化学传感性能. 玻璃态石墨烯器件探测丙酮的信噪比为48, 比石墨烯器件提 高了50%以上. 此外, 对偏压和厚度有关的挥发性有机化合物(VOC)感测功能的分析表明, 少层玻璃态石墨烯更为敏感. 这项研究表明玻璃态石墨烯在集成光电探测和化学传感多功能器件方面具有巨大应用前景.