Chen Xiaoxiao, Liu Xu, Li Shouhao, Wang Weimin, Wei Di, Wu Yongle, Liu Zhongfan
School of Electronic Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China.
Beijing Graphene Institute, Beijing, China.
Nanoscale. 2020 May 28;12(20):10949-10955. doi: 10.1039/d0nr00507j.
Nano-materials could endow electronics with some new functionalities. A slot antenna with a tunable bandwidth, consisting of a planar slot antenna with graphene at the end and a gap located between the ground and a small patch, is proposed in this study. The printed graphene inks deposited onto the antenna are made of graphene powder and graphene oxide aqueous dispersion. Graphene oxide sheets function as effective surfactants providing assistance to form uniform inks; meanwhile, the tailored blending proportions endow the graphene inks with optimized original resistances. Dried graphene inks display alterable electrical resistance under DC voltages and the variation in the resistance affects the radiation of the antenna. The slot antenna realizes an operating bandwidth (reflection coefficient |S11| < -10 dB) from 2.83 GHz to 6 GHz and a maximum frequency shift of 0.54 GHz after applying a DC voltage of less than 15 V. The graphene inks reported in this work integrate the dual advantages of graphene and graphene oxide. They not only provide stable and tunable graphene solution to antennas, but also could expand their applications in many other fields of electronic devices.
纳米材料可为电子产品赋予一些新功能。本研究提出了一种具有可调带宽的缝隙天线，它由末端带有石墨烯的平面缝隙天线以及位于接地板和小贴片之间的缝隙组成。沉积在天线上的印刷石墨烯墨水由石墨烯粉末和氧化石墨烯水分散体制成。氧化石墨烯片充当有效的表面活性剂，有助于形成均匀的墨水；同时，定制的混合比例赋予石墨烯墨水优化的初始电阻。干燥的石墨烯墨水在直流电压下显示出可变电阻，电阻的变化会影响天线的辐射。该缝隙天线在施加小于15V的直流电压后，实现了从2.83GHz到6GHz的工作带宽（反射系数|S11| < -10dB）以及0.54GHz的最大频率偏移。本工作中报道的石墨烯墨水兼具石墨烯和氧化石墨烯的双重优势。它们不仅为天线提供了稳定且可调的石墨烯溶液，还能扩展其在电子设备许多其他领域的应用。
