Incorporating porous structures into flexible piezoelectric materials has proven to be an effective strategy to enhance the output performance, but the fabrication processes are often intricate or environmentally harmful. In this study, natural sucrose with substantial hydroxyl groups was firstly introduced into polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) as a phase formation inducer, and subsequently removed by the dissolution of water as a pore formation agent, yielding a regular porous structure. Furthermore, porosity of the PVDF-HFP film could be simply modulated by adjusting the mass ratio of sucrose to PVDF-HFP. At low porosity levels, the dielectric constant of PVDF-HFP decreased with the increase of porosity, reaching the minimum at the critical threshold porosity of 38.8%. Owing to the increased β-phase content and the decreased dielectric constant, the sensitivity of the porous PVDF-HFP film based piezoelectric sensor was tripled to 117 mV/N, which held promise for detecting tactile and slip signals in mechanical arms.
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