Enhancing sensitivity of aerogel press sensors through sequential buckling Zhuofan Qin 1 , Emmanuel Omotosho 2 , Dr. Ding Wang 2 , Dr. Xue Chen 3 , Dr. Terence Xiaoteng Liu 3 , Prof. Ben Bin Xu 1*, Yuhao Wang 1 , Dr. Dong Liu 2 , Zibi Wang 3 , Prof. Fei Chen 2 1 Mechanical and Construction Engineering, Northumbria University, UK, 2 School of Chemical Engineering and Technology, Xi’an Jiaotong University, China Aerogels are a class of highly porous materials characterized by their low bulk density, unique structure and high specific surface area [1-5]. These advantages have been attracting intense attention from scientific research and industry for sensors and ideal wearable devices [6-10]. We mainly consider the Chitosan-Graphene Oxide (CS:GO) aerogel with regular microstructure and conductive network. The traditional lamella structure with micro- wave shaped layer stacked derived from simple freeze-casting and then carbonization or annealing at about 800℃ to offer aerogel with favorable resilience, which is a complex and energy-intensive production process. We improve the fabrication method by the sequential buckling strategy with post-crosslinker, which means that after freeze-casting and freeze-drying, the molecular chains are cross-linked to connect the buckled structure by chemical bonds and only 180℃ heat treatment for 3h, to obtain the crosslinked chitosan and reduced graphene oxide (CCS:rGO) aerogel with arc-like microstructure, which means the pores among microlayers provide space to withstand large deformations and recovery after deformation, thus endow the aerogels with excellent mechanical properties and sensitivity. Specific heat transformation of microstructure is illustrated by FEM simulation. References 1. S. Malakooti, et al. Synthesis of aerogel foams through a pressurized sol-gel method. Polymer 208, 122925 (2020). 2. H. Maleki, S. Montes, N. Hayati-Roodbari, F. Putz&;N. Huesing Compressible, Thermally Insulating, and Fire Retardant Aerogels through Self-Assembling Silk Fibroin Biopolymers Inside a Silica Structure—An Approach towards 3D Printing of Aerogels. ACS Applied Materials &; Interfaces 10, 22718-22730 (2018). 3. Y. Li, et al. Construction of functional cellulose aerogels via atmospheric drying chemically cross-linked and solvent exchanged cellulose nanofibrils. Chemical Engineering Journal 366, 531-538 (2019). 4. S. Karamikamkar, E. Behzadfar, H. E. Naguib&;C. B. Park Insights into in-situ sol-gel conversion in graphene modified polymer-based silica gels for multifunctional aerogels. Chemical Engineering Journal 392, 123813 (2020). 5. M. Alshrah, M.-P. Tran, P. Gong, H. E. Naguib&;C. B. Park Development of high-porosity resorcinol formaldehyde aerogels with enhanced mechanical properties through improved particle necking under CO2 supercritical conditions. Journal of Colloid and Interface Science 485, 65-74 (2017). 6. Y. Hu, et al. Biomass polymer-assisted fabrication of aerogels from MXenes with ultrahigh compression elasticity and pressure sensitivity. Journal of Materials Chemistry A 7, 10273-10281 (2019). 7. Z. Yue, et al. Sponge Graphene Aerogel Pressure Sensors with an Extremely Wide Operation Range for Human Recognition and Motion Detection. ACS Applied Electronic Materials 3, 1301-1310 (2021). 8. Z. Hanif, D. Shin, D. Choi&;S. J. Park Development of a vapor phase polymerization method using a wet-on-wet process to coat polypyrrole on never-dried nanocellulose crystals for fabrication of compression strain sensor. Chemical Engineering Journal 381, 122700 (2020). 9. H. Wei, et al. Polypyrrole/reduced graphene aerogel film for wearable piezoresisitic sensors with high sensing performances. Advanced Composites and Hybrid Materials 4, 86-95 (2021). 10. Z. He, et al. Detecting subtle yet fast skeletal muscle contractions with ultrasoft and durable graphene-based cellular materials. National Science Review (2021).
P47
© The Author(s), 2023
Made with FlippingBook Learn more on our blog