Synergistic Piezoelectric Enhancement in 3D-Printed PVDF-HFP/ZnO/CNTs Composite: Interface Engineering and Porous Architecture

Abstract Driven by the escalating demand for low-carbon development, piezoelectric parts demonstrate an irreplaceable application value due to the intrinsic capability to directly convert ubiquitous mechanical vibrations into electricity. However, the widespread application of conventional low-dimensional piezoelectric parts is constrained by restricted strain space and inherently low conversion efficiency. Herein, a high-performance 3D piezoelectric part based on a PVDF-HFP/tetrapod-like ZnO/CNTs ternary composite was successfully fabricated via the fused deposition modeling (FDM) process. The deformation evolution from the macroscopic structural level to the microscopic filler level was comprehensively analyzed through detailed experimental characterization and finite element simulations. The synergistic enhancement mechanisms arising from the multicomponent interfacial coupling and the unique structural features were systematically elucidated. The optimized open circuit voltage of 6.64 V and short circuit current of 246.2 nA were achieved, representing 10.5-fold and 11.8-fold improvements over those of the pure PVDF-HFP parts. Furthermore, the ternary composite parts demonstrated a rapid response time of 93 ms when integrated into a proof-of-concept intelligent assisted positioning system for visually impaired individuals, enabling real-time voice alerts and synchronized automatic door operation. This work presented an effective interface-structure cooperative paradigm for constructing high-performance 3D piezoelectric parts and underscored the considerable promise in the realm of human-machine interaction.