報(bào)告題目：細(xì)胞狀石墨烯的機(jī)械性能及其在傳感器中的應(yīng)用研究
Mechanical Properties of Cellular Graphene and their Sensor Applications
報(bào)告人：Kin Liao（廖堅(jiān)）教授，阿聯(lián)酋哈利法大學(xué)（Khalifa University）
報(bào)告時(shí)間：2016年8月1日（周一）9：30
報(bào)告地點(diǎn)：化學(xué)樓二樓一號(hào)會(huì)議室
Kin Liao （廖堅(jiān)）教授個(gè)人簡(jiǎn)介
Kin Liao （廖堅(jiān)）教授, 阿聯(lián)酋哈利法大學(xué)（Khalifa University）教授。Kin Liao教授在美國(guó)弗吉尼亞理工大學(xué)（Virginia Tech）本科、碩士、博士畢業(yè)，曾在美國(guó)國(guó)家標(biāo)準(zhǔn)局、西北大學(xué)工作，以李光耀學(xué)者身份在新加坡南洋理工大學(xué)任教職13年并獲終身教職職位，曾擔(dān)任新加坡南洋理工大學(xué)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(dá)比酋長(zhǎng)國(guó)的哈里發(fā)大學(xué)，任航空航天學(xué)院/機(jī)械學(xué)院雙聘正教授，哈里發(fā)大學(xué)機(jī)械系主任等職務(wù)。從事納米材料納米力學(xué)、生物分子和細(xì)胞、組織工程、活體和非活體分子應(yīng)激、纖維復(fù)合物的機(jī)械性能，新材料在能源和環(huán)境領(lǐng)域的應(yīng)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(fā)表學(xué)術(shù)論文120余篇，總的他引次數(shù)為2600次。
報(bào)告內(nèi)容: 細(xì)胞狀石墨烯的機(jī)械性能及其在傳感器中的應(yīng)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.
