VDF-content-guided selection of piezoelectric P(VDF-TrFE) films in sensing and energy harvesting applications. (1st May 2020)

• Record Type: Journal Article
• Authors: Jiang, Hanxiao; Yang, Jiang; Xu, Fan; Wang, Qinhao; Liu, Weilin; Chen, Qiusong; Wang, Conghuan; Zhang, Xiaoqing; Zhu, Guodong
• Is Part Of: Energy conversion and management. Volume 211(2020)
• Publication Date: 2020-05-01
• Subjects: Piezoelectric polymer -- P(VDF-TrFE) -- VDF content -- Energy harvesting -- Sensors; Direct energy conversion -- Periodicals; Energy storage -- Periodicals; Energy transfer -- Periodicals; Énergie -- Conversion directe -- Périodiques; Direct energy conversion; Periodicals; 621.3105
• DOI: 10.1016/j.enconman.2020.112771
• Languages: English
• ISSNs: 0196-8904

Abstract

Highlights: CVDF guides selection of copolymer materials in sensing and harvesting applications. 70/30 film has the best transverse piezoelectric property. 50/50 film has the highest longitudinal piezoelectric response. 55/45 film has the largest energy conversion efficiency. Abstract: Worldwide energy crisis and environmental pollution issues are driving people to seek for clean energy harvesting technologies as alternative and/or complementary energy sources for traditional fossil fuel, in which piezoelectric nanogenerators are extensively studied for mechanical energy harvesting due to their high energy density, simple architectures and excellent scaling-down capacity. Poly(vinylidene fluoride) (PVDF) and its copolymer with trifluoroethylene (P(VDF-TrFE)) are mostly studied piezoelectric polymers. Recent work indicated that the largest longitudinal coefficient occurred at the morphotropic phase boundary of P(VDF-TrFE) with 50 mol.% VDF content (CVDF ), while P(VDF-TrFE) with higher CVDF was mostly studied. Thus it is indispensable to further understand the influence of CVDF on piezoelectric performance in order to optimize the design of P(VDF-TrFE) based sensors and energy harvesters in various practical applications. Here we made a systematic investigation of the dependence of longitudinal and transverse piezoelectric properties on CVDF in commercially available 50/50, 55/45 and 70/30 copolymers. Experimental results indicated that 50/50 copolymer presented the largest longitudinal piezoelectric property and thus provided the best electric response for tactile sensing while 70/30 one showed the most outstanding transverse piezoelectricity and applied for monitoring the bending of fingers. In energy harvesting experiments at maximum strain of 1.2% and frequency of 0.6 Hz, 70/30 copolymer showed the largest power density of 4.96 nW/mm 2, while 55/45 copolymer had the highest energy conversion efficiency of 1.03%. Device performance was expected to be further improved by controlling film quality and microstructures.