High‐Performance Piezoelectric Nanogenerators with Imprinted P(VDF‐TrFE)/BaTiO₃ Nanocomposite Micropillars for Self‐Powered Flexible Sensors

Abstract

Piezoelectric nanogenerators with large output, high sensitivity, and good flexibility have attracted extensive interest in wearable electronics and personal healthcare. In this paper, the authors propose a high-performance flexible piezoelectric nanogenerator based on piezoelectrically enhanced nanocomposite micropillar array of polyvinylidene fluoride-trifluoroethylene (P(VDF-TrFE))/barium titanate (BaTiO ) for energy harvesting and highly sensitive self-powered sensing. By a reliable and scalable nanoimprinting process, the piezoelectrically enhanced vertically aligned P(VDF-TrFE)/BaTiO nanocomposite micropillar arrays are fabricated. The piezoelectric device exhibits enhanced voltage of 13.2 V and a current density of 0.33 µA cm , which an enhancement by a factor of 7.3 relatives to the pristine P(VDF-TrFE) bulk film. The mechanisms of high performance are mainly attributed to the enhanced piezoelectricity of the P(VDF-TrFE)/BaTiO nanocomposite materials and the improved mechanical flexibility of the micropillar array. Under mechanical impact, stable electricity is stably generated from the nanogenerator and used to drive various electronic devices to work continuously, implying its significance in the field of consumer electronic devices. Furthermore, it can be applied as self-powered flexible sensor work in a noncontact mode for detecting air pressure and wearable sensors for detecting some human vital signs including different modes of breath and heartbeat pulse, which shows its potential applications in flexible electronics and medical sciences.

A Flexible Lead‐Free BaTiO3/PDMS/C Composite Nanogenerator as a Piezoelectric Energy Harvester

“…[15][16][17] In order to solve the fragile problemso ft he PNGs,s ilk fibroin, polyvinylidene fluoride (PVDF), and polydimethyl siloxane (PDMS) are widely used as am atrix in the pure piezoelectric NPs. [18][19][20][21][22] Piezoelectric nanocomposites composedo fp iezoelectric NPs and flexible polymers have demonstrated remarkable flexibility when used in flexible devices and wearable applications. [23][24][25][26][27] For example,K im [28] reported the silk-fibroin-based biodegradable piezoelectric composite nanogenerators using lead-free ferroelectric nanoparticles (BaTiO 3 ,Z nSnO 3 ,B i 0.5 (Na 0.82 K 0.18 ) 0.5 TiO 3 ,a nd K 0.5 Na 0.5 Nb 0.995 Mn 0.005 O 3 ), which could obtain maximum output voltages and current densities of 2.2 Va nd 0.12 mAcm À2 .S hin [29] reported high-performance flexible NGs based on ac omposite thin film composed of hemispherically aggregated BaTiO 3 NPs and poly-(vinylidene fluoride-co-hexafluoropropene) P(VDF-HFP), whiche xhibited high electricalo utput up to 5Vand 750 nA by cyclic measurementu nder bending.…”

A soft lithography method to generate arrays of microstructures onto hydrogel surfaces

“…Microstructured surfaces are also used in innovative applications that include force sensors, biosensors, drug delivery systems, actuators, photonic structures, optoelectronics, piezoelectric devices, and in cellular adhesion, migration, and differentiation studies . However, use or implementation of microstructured surfaces for many biological applications is limited by the types of materials that can be patterned with such fine features because many of these materials are not biodegradable and their mechanical properties are incompatible with natural tissues.…”

Flexible and Ultrasensitive Piezoelectric Composites Based on Highly (00l)‐Assembled BaTiO3 Microplatelets for Wearable Electronics Application

“…It can be seen that the BaTiO 3 microplatelets have a relatively homogeneous microstructure and regular morphology, as well as a narrow distribution with average size of 9.1 µm. [48] With the addition of BT microparticles of 53.8 wt%, the remnant polarization of the composite film increases to 7.5 µC cm −2 . Figure 2a presents the P-E hysteresis loop of P(VDF-TrFE)/ BT single-crystal microplatelets composite film.…”