Weijun Jiang,Jingyuan Liu,Hongsen Zhang,Dalei Song,Jing Yu,Qi Liu,Rongrong Chen,Jiahui Zhu,Jun Wang
Wearable, flexible sensors based on hydrogel fabrication have recently gained significant attention due to their unique properties. However, developing hydrogel sensors that maintain high sensitivity and work effectively in sub-zero temperatures remains a formidable challenge. Herein, a hydrogel with surfaces featuring randomly distributed microspines is synthesized by combining sodium alginate (SA) and acrylamide (AM) as the hydrogel components. To fabricate a wearable sensor, a highly conductive MXene layer is inkjet-printed onto the surface of the hydrogel microspines. The resulting sensor exhibits a remarkable array of features, including exceptional sensitivity (15.03 kPa −1 ), a low detection limit (10 Pa), a vast operating range (0.12–70 kPa), rapid response and recovery (40/100 ms), reliable performance (over 1000 cycles), and outstanding resistance to low temperatures (-20 °C). Moreover, this hydrogel-based sensor facilitates the efficient collection of human monitoring data, such as vocal patterns, pulse, and joint movements, even when operating at −20 °C and in ice bath conditions. Importantly, the surface-based inkjet MXene hydrogels could be assembled into a deformable triboelectric nanogenerator (TENG), allowing mechanical energy harvesting. The TENG exhibited peak output voltage and current values of 5 V and 2.5 μA, respectively.
Inkjet printability of dye-based inks including stability, jetting morphology, and color performance is difficult to maintain due to the strong dye molecular interaction. Herein, carboxyl-rich polymer nanospheres were introduced to the dye-based inks, forming a novel kind of multilayer dye/polymer nanospheres to enhance the inkjet printability. Disperse dyes were firstly loaded into poly (styrene-butyl acrylate-methacrylate) nanospheres at 95 °C, and then encapsulated by poly (styrene-methacrylate) polymer layer through seed polymerization to form multilayer structure. The results showed that hydrogen bonds were formed between disperse dyes and nanospheres, and the interaction was enhanced when more carboxyl groups were polymerized on nanosphere surface. Moreover, due to the high surface carboxyl group content, the stability was significantly improved in comparison with disperse dye suspension. After inkjet printing , the dye/nanosphere dispersion showed more stable droplet formation and higher color depth. Besides, because of the self-curing ability of polymer nanospheres, satisfactory fastness was obtained for practical application. The results from this study can promote the optimization of dye-based ink formulations, and show great potential in obtaining high quality inkjet printing products.
危险品化学品经营许可证（带存储）