Dielectric micro-capacitance for enhancing piezoelectricity via aligning MXene sheets in composites
Guo Tian, Weili Deng, Da Xiong, Tao Yang, Binbin Zhang, Xiarong Ren, Boling Lan, Shen Zhong, Long Jin, Hongrui Zhang, Lin Deng, Weiqing Yang
Abstract
Piezoelectric polymers have attracted a great deal of attention for flexible electromechanical applications but still suffer from low piezoelectric coefficients (∼−24 pC/N) in commercial films. Here, we propose a dielectric micro-capacitance strategy to enhance piezoelectricity via texturing well-aligned MXene (Ti3C2Tx) sheets into a poly(vinylidene fluoride) (PVDF) matrix using a scalable blade-coating technique. This aligned MXene/PVDF composite presents a piezoelectric coefficient of −63.3 pC/N due to its improved permittivity. More importantly, a modified model of the piezo-composite is put forward to further understand the interfacial polarization and dielectric relaxation effect in this percolation system for designing piezo-composites with better performances. Notably, this work might motivate new design principles and approaches to regulate electric behavior and promote piezoelectricity in electroactive polymers.