Hassan Kamrul, Tung Tran Thanh, Stanley Nathan, Yap Pei Lay, Farivar Farzaneh, Rastin Hadi, Nine Md Julker, Losic Dusan
School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA 5005, Australia.
Nanoscale. 2021 Mar 18;13(10):5356-5368. doi: 10.1039/d1nr00150g.
Printed electronic sensors offer a breakthrough in the availability of low-cost sensor devices for improving the quality of human life. Conductive ink is the core of printing technology and also one of the fastest growing sector among all ink industries. Among many developed conductive inks, graphene-based inks are especially recognized as very promising for future fabrication of devices due to their low cost, unique properties, and compatibility with various platforms such as plastics, textiles, and paper. The development of graphene ink formulations for achieving high conductivity and high resolution printing is highly realized in 2D inkjet printing. Unfortunately, the ongoing development of graphene inks is possibly hampered by the non-uniform particle size and structures (e.g., different shapes and number of layers), which adversely affect printing resolution, conductivity, adhesion, and structural integrity. This study presents an environmentally sustainable route to produce graphene inks specifically designed for 3D extrusion-printing. The application of the prepared ink is demonstrated by mask-free automatic patterning of sensing devices for the detection of volatile organic compounds (VOCs). The sensing devices fabricated with this new ink display high-resolution patterning (average height/thickness of ∼12 μm) and a 10-fold improvement in the surface area/volume (SA/V) ratio compared to a conventional drop casting method. The extrusion printed sensors show enhanced sensing characteristics in terms of sensitivity and selectivity towards trace amount of VOC (e.g. 5 ppm ethanol) at room temperature (20 °C), which highlights that our method has highly promising potential in graphene printing technology for sensing applications.
印刷电子传感器为改善人类生活质量的低成本传感器设备的可用性带来了突破。导电油墨是印刷技术的核心，也是所有油墨行业中发展最快的领域之一。在众多已开发的导电油墨中，基于石墨烯的油墨因其低成本、独特性能以及与塑料、纺织品和纸张等各种平台的兼容性，尤其被认为在未来设备制造方面极具潜力。在二维喷墨印刷中，为实现高导电性和高分辨率印刷而开发的石墨烯油墨配方已得到高度认可。不幸的是，石墨烯油墨的持续发展可能受到颗粒尺寸和结构不均匀（例如不同形状和层数）的阻碍，这对印刷分辨率、导电性、附着力和结构完整性产生不利影响。本研究提出了一种环境可持续的路线来生产专门为三维挤压印刷设计的石墨烯油墨。通过对用于检测挥发性有机化合物（VOCs）的传感设备进行无掩膜自动图案化，展示了所制备油墨的应用。与传统的滴铸法相比，用这种新油墨制造的传感设备显示出高分辨率图案（平均高度/厚度约为12μm），并且表面积/体积（SA/V）比提高了10倍。挤压印刷传感器在室温（20°C）下对痕量VOC（例如5ppm乙醇）的灵敏度和选择性方面表现出增强的传感特性，这突出表明我们的方法在用于传感应用的石墨烯印刷技术中具有极具潜力的前景。
