Speech Title: Multifunctional Hydrogel Based Flexible Sensor
Biography: Professor Min Xu of East China Normal University (ECNU) is currently the Vice Dean of school of physics and electronic sciences. She received her PhD in chemistry from Nanjing University. Then she worked as a Postdoc in ECNU, and then be associate professor, professor of ECNU. She also worked as research fellow in Nanyang technological university (2004-2006) and visiting scholar in the University of Akron (2016-2017). She is now the editorial board member of “functional polymer materials”, committee member of polymer characterization council of Chinese Chemistry Society (CCS) and Cellulose council of CCS.
Her research focus on polymer composite materials, especially natural polymer composite materials, including adsorption materials, multi-functional hydrogels, natural polymer based smart sensors and supercapacitors applied for flexible and wearable devices. Besides, she is skilled in mechanism study with solid-state NMR.
Abstract: In this paper, a multifunctional flexible strain sensor basing on hydrogel was reported. A double network was designed by in-situ polymerization of [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (SBMA) in bacterial cellulose nanofibers (BCN) aqueous dispersion. Due to the whole biomass based materials, the obtained hydrogel PSBMA@BCN shows excellent biocompatibility. Benefiting from the numerous zwitterionic functional groups, the PSBMA@BCN hydrogel also shows great anti-swelling and self-adhesion performance. The resistance of PSBMA@BCN hydrogel shows almost linear dependence on the strain ranging from 0 to 150%. Based on the hydrogel sensor, an intelligent communication system is developed to achieve information transmission. The assembled PSBMA@BCN flexible wearable device can precisely respond to target movement and output signals in real time so that the hydrogel can play a role in monitoring and identifying different target movement. More significantly, the anti-swelling properties make the wearable electronic device can be applied even in underwater condition, the hydrogel sensor can not only realize real-time monitoring and identification of target movement, but can also achieve intelligently underwater communication through the combination of computer programming and circuit design. As such, the biocompatibility hydrogel sensor has broad application prospects in underwater environment, providing a promising route to promote the development of next-generation wearable devices.
Prof. Yang Gao, East China University of Science and Technology, China
Speech Title: Laser Microfabrication of Flexible Sensors
Biography: Prof. Yang Gao received the B.S. and the M.S. degrees from East China Normal University, Shanghai, China, in 2005 and 2008, respectively, and PhD degrees from University of Nebraska-Lincoln, USA, in 2013. From 2013 to 2014, and 2014 to 2016, he is postdoctoral fellow in University of Nebraska-Lincoln and University of Houston, respectively. Since 2016, he is, respectively, an Assistant Professor and a Full Professor at School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai China. He is the author or co-author of 80 papers published in international journals.
Abstract: In recent years, flexible sensors gain much attentions due to its capability of mimicking human skins for perceiving, distinguishing, and transmitting various external stimuli, which have promising applications in human-machine interfaces, internet of things and structural health monitoring. To accomplish the aforementioned applications, not only high sensitivity, fast response speed and mechanical robustness are demanded for the sensors, but also a highly efficient and scalable fabrication method is desired for wide adoption of the sensors.
In this talk, laser-based microfabrication method was developed to fabricate flexible sensors, which has been proved to be high-throughput and scalable. Firstly, a laser direct writing technique is developed to fabricate high-performance strain sensors directly on flexible substrates including polyimide, Ecoflex film, etc.. Then, a laser microengineering method is developed to introduce microstructures into flexible pressures for enhanced sensitivity and response time. Finally, the potential applications of the sensors in status monitoring of hydrogen storage vessel for fuel cell autocycle is presented.