In situ rapid gelation and osmotic dehydration-assisted preparation of graphene aerogel and its application in piezoresistive sensors

This study presents a straightforward and rapid method for preparing graphene aerogel by integrating a sodium alginate (SA)-metal ion crosslinking system, a bubble template, and an osmotic dehydration process. Graphene
oxide (GO) nanosheets were dispersed into the solution crosslinked by SA and metal ions, leading to rapid gelation of GO under ambient conditions. To minimize structural damage to the porous network caused by water
molecules during the drying process, an osmotic dehydration technique was employed as an auxiliary drying method. This, combined with ambient-pressure drying, significantly improved both drying efficiency and
structural integrity of the aerogel. The incorporation of the bubble template was crucial in stabilizing the pore structure by mitigating capillary forces. Following high-temperature thermal reduction, highly ordered and
porous reduced GO aerogels were successfully obtained. Additionally, the potential application of these aerogels in the field of piezoresistive sensors was explored. This method provides a low-cost, efficient, and versatile
approach of GA fabrication, offering promising prospects for a wide range of applications.