A Simple, Rapid, and Green Method for Preparing Highly Conductive Reduced Graphene Oxide Aerogel for Pressure Sensors

Due to its excellent performance, reduced graphene oxide aerogel (rGA) has been widely used in recent years. Typically, the mechanical and electrical properties of graphene oxide can be enhanced through doping, compositing, or heat treatment. This work presents a simple, fast, and environmentally friendly method for producing high-performance rGA using two reducing agents. During the reduction process, ascorbic acid can cross-link and reduce graphene oxide, while the reducing ability of ammonium citrate restores the conjugated structure of the graphene sheets. By fixing the concentration of ascorbic acid and adjusting the amount of ammonium citrate, we can obtain DrGA-2 that possesses both mechanical and electrical properties. The maximum strain and stress of DrGA-2 are 40.0% and 21.5 kPa, respectively. Meanwhile, only a 10% compressive strain is sufficient to induce a 95% resistance change rate. When DrGA-2 is assembled into a capacitive sensor, its capacitance change rate ranges from 80% to 200% under different strain conditions, enabling real-time monitoring of subtle human movements. This demonstrates the tremendous potential of this material in this field.