Vertically aligned P(VDF-TrFE) core-shell structures on flexible pillar arrays

PVDF and P(VDF-TrFE) nano- and micro- structures have been widely used due to their potential applications in several fields, including sensors, actuators, vital sign transducers, and energy harvesters. In this study, we developed vertically aligned P(VDF-TrFE) core-shell structures using high modulus polyurethane acrylate (PUA) pillars as the support structure to maintain the structural integrity. In addition, we were able to improve the piezoelectric effect by 1.85 times from 40 ± 2 to 74 ± 2 pm/V when compared to the thin film counterpart, which contributes to the more efficient current generation under a given stress, by making an effective use of the P(VDF-TrFE) thin top layer as well as the side walls. We attribute the enhancement of piezoelectric effects to the contributions from the shell component and the strain confinement effect, which was supported by our modeling results. We envision that these organic-based P(VDF-TrFE) core-shell structures will be used widely as 3D sensors and power generators because they are optimized for current generations by utilizing all surface areas, including the side walls of core-shell structures.

[1]  Eun Kyung Lee,et al.  Porous PVDF as effective sonic wave driven nanogenerators. , 2011, Nano letters.

[2]  Dipankar Mandal,et al.  Origin of piezoelectricity in an electrospun poly(vinylidene fluoride-trifluoroethylene) nanofiber web-based nanogenerator and nano-pressure sensor. , 2011, Macromolecular rapid communications.

[3]  Xingzhong Zhao,et al.  Fabrication and characterization of Ni/P(VDF-TrFE) nanoscaled coaxial cables , 2007 .

[4]  Sicong Shan,et al.  A multipeak phenomenon of magnetoelectric coupling in Terfenol-D/P(VDF-TrFE)/Terfenol-D laminates , 2010 .

[5]  K. No,et al.  Nanoscale piezoresponse of 70 nm poly(vinylidene fluoride‐trifluoro‐ethylene) films annealed at different temperatures , 2010 .

[6]  Bernd Fischer,et al.  High-Temperature Mechanical Properties of the Platinum Group Metals , 2006 .

[7]  Rui Zhang,et al.  Characterization of piezoelectric materials with large piezoelectric and electromechanical coupling coefficients. , 2003, Ultrasonics.

[8]  K. Suh,et al.  Precise tip shape transformation of nanopillars for enhanced dry adhesion strength , 2012 .

[9]  A. K. Bhaduri,et al.  Direct observation of amophization in load rate dependent nanoindentation studies of crystalline Si , 2010 .

[10]  Joseph A. Paradiso,et al.  Energy scavenging for mobile and wireless electronics , 2005, IEEE Pervasive Computing.

[11]  A. Authier,et al.  Physical properties of crystals , 2007 .

[12]  Arnan Mitchell,et al.  Nanoscale Characterization of Energy Generation from Piezoelectric Thin Films , 2011 .

[13]  Yi Qi,et al.  Nanotechnology-enabled flexible and biocompatible energy harvesting , 2010 .

[14]  J. Nye Physical Properties of Crystals: Their Representation by Tensors and Matrices , 1957 .

[15]  Xin Zhou,et al.  A Dielectric Polymer with High Electric Energy Density and Fast Discharge Speed , 2006, Science.

[16]  Tae Hyun Sung,et al.  Spin-coated ultrathin poly(vinylidene fluoride-co-trifluoroethylene) films for flexible and transparent electronics , 2011 .

[17]  M. Willander,et al.  Nanoscale piezoelectric response of ZnO nanowires measured using a nanoindentation technique. , 2013, Physical chemistry chemical physics : PCCP.

[18]  Youn Jung Park,et al.  Non-volatile memory characteristics of epitaxially grown PVDF-TrFE thin films and their printed micropattern application , 2011 .

[19]  Zhijun Hu,et al.  Regular arrays of highly ordered ferroelectric polymer nanostructures for non-volatile low-voltage memories. , 2009, Nature materials.

[20]  K. Kim,et al.  An infra-red spectroscopic study of structural reorganization of a uniaxially drawn VDF/TrFE copolymer in an electric field , 1994 .

[21]  H. Ishiwara,et al.  Low-voltage operation of ferroelectric poly(vinylidene fluoride-trifluoroethylene) copolymer capacitors and metal-ferroelectric-insulator-semiconductor diodes , 2007 .

[22]  L. E. Cross,et al.  Piezoelectric, dielectric, and elastic properties of poly(vinylidene fluoride/trifluoroethylene) , 1993 .

[23]  Qiming Zhang,et al.  Structural, Conformational, and Polarization Changes of Poly(vinylidene fluoride−trifluoroethylene) Copolymer Induced by High-Energy Electron Irradiation , 2000 .

[24]  D. Gallego-Perez,et al.  Versatile methods for the fabrication of polyvinylidene fluoride microstructures , 2010, Biomedical microdevices.

[25]  Qian Li,et al.  Nano‐Imprinted Ferroelectric Polymer Nanodot Arrays for High Density Data Storage , 2013 .

[26]  王军波,et al.  Direct-Write Piezoelectric Polymeric Nanogenerator with High Energy Conversion Efficiency , 2010 .