報告題目：細胞狀石墨烯的機械性能及其在傳感器中的應用研究
Mechanical Properties of Cellular Graphene and their Sensor Applications
報告人：Kin Liao（廖堅）教授，阿聯酋哈利法大學（Khalifa University）
報告時間：2016年8月1日（周一）9：30
報告地點：化學樓二樓一號會議室
Kin Liao （廖堅）教授個人簡介
Kin Liao （廖堅）教授, 阿聯酋哈利法大學（Khalifa University）教授。Kin Liao教授在美國弗吉尼亞理工大學（Virginia Tech）本科、碩士、博士畢業，曾在美國國家標準局、西北大學工作，以李光耀學者身份在新加坡南洋理工大學任教職13年并獲終身教職職位，曾擔任新加坡南洋理工大學生物工程系副主任，生物信息研究中心主任，而后加入阿布達比酋長國的哈里發大學，任航空航天學院/機械學院雙聘正教授，哈里發大學機械系主任等職務。從事納米材料納米力學、生物分子和細胞、組織工程、活體和非活體分子應激、纖維復合物的機械性能，新材料在能源和環境領域的應用及3D打印等方面的研究工作。至今為止在Advanced Materials, Nano Letters, Applied Physics Letters等刊物上共發表學術論文120余篇，總的他引次數為2600次。
報告內容: 細胞狀石墨烯的機械性能及其在傳感器中的應用研究
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.
