Superelastic Graphene Aerogels Constructed by Structural Modulation for Piezoresistive Sensing

The microstructure is a critical factor in determining the macroscopic properties of aerogel materials and has a significant impact on their performance in various application scenarios. Here, drawing inspiration from the microstructure regulation of the bubble template, polyvinylpyrrolidone (PVP) was used to microscopically regulate graphene oxide nanosheets in the fabrication of the graphene aerogel (GA). Simultaneously, sodium dodecyl sulfate (SDS) foaming was employed as the bubble template to aid in the construction of PVP/SDS-GA (PSGA) with a hierarchical porous structure. Such an innovative structural blueprint inherently promotes a more even distribution of stress, thereby enhancing the compressive strength of the aerogel. The advanced architecture of PSGA enables rapid desiccation by using ambient pressure and elevated thermal methods, simplifying the fabrication process. PSGA possesses several remarkable characteristics: an ultralow density of 2.84 mg/cm3, a high electrical conductivity of 10 S/m, a superelasticity with an extreme strain of 99%, an outstanding fatigue resistance with the ability to withstand 10,000 cycles at 70% strain, and a high compressive strength of 0.66 MPa. In light of these characteristics, the piezoresistive sensor conceptualized using PSGA as a foundational substrate exhibited superior signal discernment capabilities.