A durable and stable piezoelectric nanogenerator with nanocomposite nanofibers embedded in an elastomer under high loading for a self-powered sensor system. (December 2016)

• Record Type: Journal Article
• Authors: Siddiqui, Saqib; Kim, Do-Il; Roh, Eun; Duy, Le Thai; Trung, Tran Quang; Nguyen, Minh Triet; Lee, Nae-Eung
• Is Part Of: Nano energy. Volume 30(2016:Dec.)
• Page Start: 434
• Page End: 442
• Publication Date: 2016-12
• Subjects: Piezoelectric nanogenerator -- Nanocomposite nanofibers -- Biomechanical energy harvesting -- Energy storage -- Self-powered sensing systems; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2016.10.034
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Practical usage of piezoelectric nanogenerators (PENGs) under heavy loading environments for high power generation, such as smart shoes, has been limited due to the low mechanical endurance of many piezoelectric materials. Durability and performance under harsh environments are a stumbling block for the practical application of PENGs. Synthesis of piezoelectrically enhanced nanofibers electrospun from nanocomposite of barium titanate nanoparticles (BT NPs) dispersed in poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) enables successful fabrication of a robust, efficient, flexible and lead-free PENG. A nanofiber PENG (nf-PENG) fabricated by embedding nanocomposite nanofibers in an elastomer film is demonstrated for biomechanical energy harvesting and storage during walking. When placed inside of a shoe, a nf-PENG loaded with 15 wt% BT NPs can generate an output of 25 V at a walking frequency of 0.6 Hz with high mechanical durability under very high loads (600 N). This can charge a 4.7 µF capacitor after approximately 72 steps. The stored charge can operate a strain sensor without any external power supply. The high performance of the nf-PENG is mainly attributed to the self-poled nanocomposite nanofibers. Additionally, embedding the nanofibers into an elastomer provided high durability by protecting the nanofibers from mechanical damage. Furthermore, the devices small form factor, flexibility, and transparency make this nf-PENG suitable for applications in wearable electronics, where aesthetics and comfort are also desired (in addition to performance). This work demonstrates the possibility of highly durable, efficient, and self-powered wearable sensing systems that can work under extreme environments. Graphical abstract: A highly durable, efficient and flexible piezoelectric nanogenerator, comprised of piezoelectric nanocomposite nanofibers embedded into an elastomer, was designed for energy harvesting under heavy loading conditions. The high resistance of the generator to ambient conditions for prolonged periods of time, as well as resistance to damage under heavy loading conditions, enabled the efficient harvest of bio-mechanical energy during human walking. This energy could be stored in a capacitor to create a self-powered sensor system. This approach may help enable practical applications of piezoelectric nanogenerators in wearable systems. Highlights: Lead-free piezoelectric nanocomposite nanofibers. High durability under harsh environments and high loadings. Harvesting and storing biomechanical energy during walking. Self-powered system.