Chinese Academy of Sciences in the preparation of printed wearable sensor progress in the study to identify high-precision facial expressions

With the popularization of smart terminals, wearable electronic devices have shown great market prospects. As the most important core component of wearable devices, sensors will have a significant impact on their future functional development. As sensors move toward miniaturization, intelligence, networking and versatility, highly integrated sensors that measure multiple parameters simultaneously require innovations in manufacturing processes and analytical techniques. Printing technology is an effective way to realize the patterning of materials. However, the manufacturing precision of traditional printing technology is usually tens of micrometers, and it needs to go through complex and easy-to-pollute processes such as photolithography, greatly limiting its application in the manufacture of micro-nano devices Applications. With the strong support from the National Natural Science Foundation, the Ministry of Science and Technology and the Chinese Academy of Sciences, Song Yanlin, a researcher at the Key Laboratory of Green Printing, Institute of Chemistry, CAS, has been dedicated to promoting the green and functional development of printing technology in recent years. In functional nanomaterials Controlled assembly, fine patterning, printed electronics and device applications (Adv. Mater. 2014, 26, 6950-6958). By constructing a microscale template structure, the rupture of the liquid film on the surface of the substrate is controlled and an accurately assembled nanoparticle pattern is obtained (Adv. Mater., 26, 2501-2507); the "coffee ring" Metal nanoparticle patterns up to 5 μm in width (Adv. Mater. 2013, 25, 6714-6718); patterns with a special three-dimensional structure were prepared using the three-phase line slippage of ink. On the basis of the above research, they break through the limitation of the template and precision in the traditional printing technology, use the micro-column array as the "printing plate", and build the printing plate similar to the traditional printing process with the "ink" and the flexible substrate containing the nano- , Ink and paper "sandwich structure. With the volatilization of the solvent, the gas-liquid-solid three-phase contact lines shrink in an orderly manner, and the nano-particles are assembled on the substrate to form an array of conductive nano-scale conductive traces with precisely controlled periods and amplitudes, and are thus sensitive to micro-deformation Resistive sensor (Figure 1). The sensor attached to the monitor's skin for data acquisition and analysis, real-time monitoring of human body under different environmental and psychological conditions related to micro-physiological response, such as complex expression recognition (Figure 2), and is expected to be used in pulse monitoring , Heart monitoring and remote control and other fields. This high-precision, high-sensitivity sensor manufacturing method of printing breakthroughs in the accuracy of the traditional printing technology limits, will effectively promote the manufacture of printed wearable electronics and other micro-nano functional device development and application. The research was published as a VIP article on the recently published "Advanced Materials" (Adv. Mater. 2016, 28, 1369-1374).