Multiresponsive 3D Structured PVDF Cube Switches for Security Systems Using Piezoelectric Anisotropy

ACS Appl Mater Interfaces. 2023 Aug 16;15(32):38550-38561. doi: 10.1021/acsami.3c03377. Epub 2023 Aug 3.

Abstract

Advancements in flexible electronics using piezoelectric materials have paved the way for numerous applications. In this study, we suggest a three-dimensional (3D) structured poly(vinylidene fluoride) (PVDF) film cube switch to maximize piezoelectric anisotropy and flexibility. Unlike piezoelectric material-based flexible electronics, PVDF cube switches have a simple design and easy fabrication process. Each side of the cube switch demonstrates independent voltage signals with pressing displacements and corresponding directions. With cutting angle variations and planar figure designs, derived cube switches respond with various combinations of voltage waveforms. PVDF switches can endure more than 1000 cycles of 70% vertical strain in terms of both electrical responses and mechanical operations. As an application, we establish a security system with multiresponsibility of a cube switch. This security system can protect users from potential threats owing to its multiresponsibility and user-dependent operability.

Keywords: 3D structure; PVDF film; anisotropy; cube switch; flexible electronics; multiresponsive; origami.