报告题目：细胞状石墨烯的机械性能及其在传感器中的应用研究
Mechanical Properties of Cellular Graphene and their Sensor Applications
报告人：Kin Liao（廖坚）教授，阿联酋哈利法大学（Khalifa University）
报告时间：2016年8月1日（周一）9：30
报告地点：化学楼二楼一号会议室
Kin Liao （廖坚）教授个人简介
Kin Liao （廖坚）教授, 阿联酋哈利法大学（Khalifa University）教授。Kin Liao教授在美国弗吉尼亚理工大学（Virginia Tech）本科、硕士、博士毕业，曾在美国国家标准局、西北大学工作，以李光耀学者身份在新加坡南洋理工大学任教职13年并获终身教职职位，曾担任新加坡南洋理工大学生物工程系副主任，生物信息研究中心主任，而后加入阿布达比酋长国的哈里发大学，任航空航天学院/机械学院双聘正教授，哈里发大学机械系主任等职务。从事纳米材料纳米力学、生物分子和细胞、组织工程、活体和非活体分子应激、纤维复合物的机械性能，新材料在能源和环境领域的应用及3D打印等方面的研究工作。至今为止在Advanced Materials, Nano Letters, Applied Physics Letters等刊物上共发表学术论文120余篇，总的他引次数为2600次。
报告内容: 细胞状石墨烯的机械性能及其在传感器中的应用研究
Mechanical Properties of Cellular Graphene and their Sensor Applications
In this talk we focus on the mechanical properties of cellular graphene (CG), and the applications of graphene, and cellular graphene for sensors. We report a novel, facile, two-step, adaptable and scalable method of preparing free-standing CG with tunable densities and adjustable shapes and sizes. The CG samples fabricated possess some interesting mechanical behaviors as well as excellent electrical conductivities, reaching 160 S/m, and show insignificant decrease in electrical conductivities when infiltrated with high viscosity PDMS. The GF-PDMS composite was tested for its application as strain/pressure sensor. The composite loaded in compression shows large changes in resistance in response to application of small strains or pressures. Different densities of GF show different sensitivity to applied compressive strain/pressure; therefore, these GF-PDMS composite can be used for a range of low and high strain/pressure sensing applications.
We also report that simple sewing thread fibers and fiber mats such as Nylon® can be used as supersensitive and durable pressure and strain sensors after a slight modification with reduced graphene oxide (rGO). Pristine Nylon® fibers were coated with rGO by a novel electrostatic coating method. The rGO coated fabric show smooth coating discretely wrapping every fiber downright. The in situ twisting of the fiber observed under a scanning electron microscope shows that the rGO coating remains intact even after twisting the fiber to angles as high as 1800°. These electrically conductive fabrics have several potential applications in wearable electronic devices. We show that these rGO coated fabric and fibers are highly sensitive to external perturbation such as force or strain. The fabric’s response to applied compressive and bending stresses is recorded as the change in resistance. Single rGO coated single fibers, about 15 ?m in diameter, were isolated from the fabric and were tested for their response to flexural strains. These fibers were found to sense small strains by changing the resistance in several kilo ohms. With the help of a simple circuit it is also demonstrated that the individual rGO coated fibers, arranged in a 2x2 grid and insulated from each other, can also sense the position of the applied force.
