Browse > Article
http://dx.doi.org/10.7234/composres.2021.34.6.357

Composite-Based Material and Process Technology Review for Improving Performance of Piezoelectric Energy Harvester  

Kim, Geon Su (Department of Organic Materials and Textile Engineering, Jeonbuk National University)
Jang, Ji-un (Department of Organic and Nano Engineering, Hanyang University)
Kim, Seong Yun (Department of Organic Materials and Textile Engineering, Jeonbuk National University)
Publication Information
Composites Research / v.34, no.6, 2021 , pp. 357-372 More about this Journal
Abstract
The energy harvesting device is known to be promising as an alternative to solve the resource shortage caused by the depletion of petroleum resources. In order to overcome the limitations (environmental pollution and low mechanical properties) of piezoelectric elements capable of converting mechanical motion into electrical energy, many studies have been conducted on a polymer matrix-based composite piezoelectric energy harvesting device. In this paper, the output performance and related applications of the reported piezoelectric composites are reviewed based on the applied materials and processes. As for the piezoelectric fillers, zinc oxide, which is advantageous in terms of eco-friendliness, biocompatibility, and flexibility, as well as ceramic fillers based on lead zirconate titanate and barium titanate, were reviewed. The polymer matrix was classified into piezoelectric polymers composed of polyvinylidene fluoride and copolymers, and flexible polymers based on epoxy and polydimethylsiloxane, to discuss piezoelectric synergy of composite materials and improvement of piezoelectric output by high external force application, respectively. In addition, the effect of improving the conductivity or the mechanical properties of composite material by the application of a metal or carbon-based secondary filler on the output performance of the piezoelectric harvesting device was explained in terms of the structure of the composite material. Composite material-based piezoelectric harvesting devices, which can be applied to small electronic devices, smart sensors, and medicine with improved performance, can provide potential insights as a power source for wireless electronic devices expected to be encountered in future daily life.
Keywords
Piezoelectric harvester; Composite; Piezoelectric filler; Polymer matrix;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Yang, T., Pan, H., Tian, G., Zhang, B., Xiong, D., Gao, Y., Yan, C., Chu, X., Chen, N., Zhong, S., Zhang, L., Deng, W., and Yang, W., "Hierarchically Structured PVDF/ZnO Core-Shell Nanofibers for Self-Powered Physiological Monitoring Electronics," Nano Energy, Vol. 72, 2020, 104706.   DOI
2 Deng, W., Yang, T., Jin, L., Yan, C., Huang, H., Chu, X., Wang, Z., Xiong, D., Tian, G., Gao, Y., Zhang, H., and Yang, W., "Cowpea-Structured PVDF/ZnO Nanofibers Based Flexible Self-Powered Piezoelectric Bending Motion Sensor Towards Remote Control of Gestures," Nano Energy, Vol. 55, 2019, pp. 516-525.   DOI
3 Park, K.I., Bae, S.B., Yang, S.H., Lee, H.I., Lee, K.S., and Lee, S.J., "Lead-Free BaTiO3 Nanowires-Based Flexible Nanocomposite Generator," Nanoscale, Vol. 6, No. 15, 2014, pp. 8962-8968.   DOI
4 Shin, S.H., Kim, Y.H., Lee, M.H., Jung, J.Y., Seol, J.H., and Nah, J.H., "Lithium-Doped Zinc Oxide Nanowires-Polymer Composite for High Performance Flexible Piezoelectric Nanogenerator," ACS Nano, Vol. 8, No. 10, 2014, pp. 10844-10850.   DOI
5 Sun, H., Tian, H., Yang, Y., Xie, D., Zhang, Y.C., Liu, X., Ma, S., Zhao, H.M., and Ren, T.L., "A Novel Flexible Nanogenerator Made of ZnO Nanoparticles and Multiwall Carbon Nanotube," Nanoscale, Vol. 5, 2013, pp. 6117-6123.   DOI
6 Batra, A.K., Edwards, M.E., Alomari, A., and Elkhaldy, A., "Dielectric Behavior of P(VDF-TrFE)/PZT Nanocomposites Films Doped with Multi-walled Carbon Nanotubes (MWCNT)," American Journal of Materials Science, Vol. 5, No. 3A, 2015, pp. 55-61.
7 Yan, J., Liu, M., Jeong, Y.G., Kang, W., Li, L., Zhao, Y., Deng, N., Cheng, B., and Yang, G., "Performance Enhancements in Poly(vinylidene fluoride)-Based Piezoelectric Nanogenerators for Efficient Energy Harvesting," Nano Eneray, Vol. 56, 2019, pp. 662-692.   DOI
8 Sharma, M., Srinivas, V., Madras, G., and Bose, S., "Outstanding Dielectric Constant and Piezoelectric Coefficient in Electrospun Nanofiber Mats of PVDF Containing Silver Decorated Multiwall Carbon Nanotubes: Assessing Through Piezoresponse Force Microscopy," RCS Advances, Vol. 6, No. 8, 2016, pp. 6251-6258.
9 Su, Y.F., Kotian, R.R., and Lu, N., "Energy Harvesting Potential of Bendable Concrete using Polymer Based Piezoelectric Generator," Composites Part B: Engineering, Vol. 153, 2018, pp. 124-129.   DOI
10 Wu, N., Bao, B., and Wang, Q., "Review on Engineering Structural Designs for Efficient Piezoelectric Energy Harvesting to Obtain High Power Output," Engineering Structures, Vol. 235, 2021, 112068.   DOI
11 Sezer, N., and Koc, M., "A Comprehensive Review on the State-of-the-art of Piezoelectric Energy Harvesting," Nano Energy, Vol. 80, 2021, 105567.   DOI
12 Yang, Z., Zhou, S., Zu, J., and Inman, D., "High-Performance Piezoelectric Energy Harvesters and Their Applications," Joule, Vol. 2, No. 4, 2018, pp. 642-697.   DOI
13 Jeong, C.Y., Joung, C.W., Lee, S.H., Feng, M.Q., and Park, Y.B., "Carbon Nanocomposite Based Mechanical Sensing and Energy Harvesting," International Journal of Precision Engineering and Manufacturing-Green Technology, Vol. 7, 2020, pp. 247-267.   DOI
14 Peng, Y., Xu, Z., Wang, M., Li, Z., Peng, J., Luo, J., Xie, S., Pu, H., and Yang, Z., "Investigation of Frequency-Up Conversion Effect on the Performance Improvement of Stack-Based Piezoelectric Generators," Renewable Energy, Vol. 172, 2021, pp. 551-563.   DOI
15 Kang, M.G., Jung, W.S., Kang, C.Y., and Yoon, S.J., "Recent Progress on PZT Based Piezoelectric Energy Harvesting Technologies," Actuators, Vol. 5, No. 1, 2016, 5.   DOI
16 Pandey, R., Raj, N.P.M.J., Singh, V., Anand, P.L., and Kim, S.J., "Novel Interfacial Bulk Heterojunction Technique for Enhanced Response in ZnO Nanogenerator," ACS Applied Materials & Interfaces, Vol. 11, No. 6, 2019, pp. 6078-6088.   DOI
17 Huang, L., Lin, S., Xu, Z., Zhou, H., Duan, J., Hu, B., and Zhou, J., "Fiber-Based Energy Conversion Devices for Human-Body Energy Harvesting," Advanced Materials, Vol. 32, 2020, 1902034.   DOI
18 Xu, Z., Liu, Y., Dong, L., Closson, A.B., Hao, N., Oglesby, M., Escobar, G.P., Fu, S., Han, X., Wen, C., Liu, J., Feldman, M.D., Chen, Z., and Zhang, J.X.J., "Tunable Buckled Beams with Mesoporous PVDF-TrFE/SWCNT Composite Film for Energy Harvesting," ACS Applied Materials & Interfaces, Vol. 10, No. 39, 2018, pp. 33516-33522.   DOI
19 Le, A.T., Ahmadipour, M., and Pung, S.Y., "A Review on ZnO-Based Piezoelectric Nanogenerators: Synthesis, Characterization Techniques, Performance Enhancement and Applications," Journal of Alloys and Compounds, Vol. 844, 2020, 156172.   DOI
20 Kumar, M., Social, Economic, and Environmental Impacts of Renewable Energy Resources, Intechopen Pub. Co., London, UK, 2020.
21 Hu, D., Yao, M., Fan, Y., Ma, C., Fan, M., and Liu, M., "Strategies to Achieve High Performance Piezoelectric Nanogenerators," Nano Energy, Vol. 55, 2019, pp. 288-304.   DOI
22 Manjon-Sanz, A.M., and Dolgos, M.R., "Applications of Piezoelectrics: Old and New," Chemistry of Materials, Vol. 30, No. 24, 2018, pp. 8717-8984.   DOI
23 Shi, K., Chai, B., Zou, H., Shen, P., Sun, B., Jiang, P., Shi, Z., and Huang, X., "Interface Induced Performance Enhancement in Flexible BaTiO3/PVDF-TrFE Based Piezoelectric Nanogenerators," Nano Energy, Vol. 80, 2021, 105515.   DOI
24 Zhang, G., Liao, Q., Zhang, Z., Liang, Q., Zhao, Y., Zheng, X., and Zhang, Y., "Novel Piezoelectric Paper-Based Flexible Nanogenerators Composed of BaTiO3 Nanoparticles and Bacterial Cellulose," Advanced Science, Vol. 3, No. 2, 2016, 1500257.   DOI
25 Alluri, N.R., Selvarajan, S., Chandrasekhar, A., Saravanakumar, B., Jeong, J.H., and Kim, S.J., "Piezoelectric BaTiO3/Alginate Spherical Composite Beads for Energy Harvesting and Self-Powered Wearable Flexion Sensor," Composites Science and Technology, Vol. 142, 2017, pp. 65-78.   DOI
26 Wu, J., Qin, N., and Bao, D., "Effective Enhancement of Piezocatalytic Activity of BaTiO3 Nanowires under Ultrasonic Vibration," Nano Energy, Vol. 45, 2018, pp. 44-51.   DOI
27 Wang, X., Sun, F., Yin, C., Wang, Y., Liu, B., and Dong, M., "Tactile-Sensing Based on Flexible PVDF Nanofibers via Electrospinning: A Review," Sensors, Vol. 18, 2018, 330.   DOI
28 Li, C., Luo, W., Liu, X., Xu, D., and He, K., "PMN-PT/PVDF Nanocomposite for High Output Nanogenerator Applications," Nanomaterials, Vol. 6, No. 4, 2016, 67.   DOI
29 Zhao, Y., Liao, Q., Zhang, G., Zhang, Z., Liang, Q., Liao, X., and Zhang, Y., "High Output Piezoelectric Nanocomposite Generators Composed of Oriented BaTiO3 NPs@PVDF," Nano Energy, Vol. 11, 2015, pp. 719-727.   DOI
30 Smith, W.A., Shaulov, A., and Auld, B.A., Tailoring the Properties of Composite Piezoelectric Materials for Medical Ultrasonic Transducers, IEEE Pub. Co., New Jersey, USA, 1985.
31 Zhu, N., and West, A.R., "Formation and Stability of Ferroelectric BaTi2O5," Journal of the American Ceramic Society, Vol. 93, No. 1, 2010, pp. 295-300.   DOI
32 Chen, X., Li, X., Shao, J., An, N., Tian, H., Wang, C., Han, T., Wang, L., and Lu, B., "High-Performance Piezoelectric Nanogenerators with Imprinted P(VDF-TrFE)/BaTiO3 Nanocomposite Micropillars for Self-Powered Flexible Sensors," Small, Vol. 13, No. 23, 2017, 1604245.   DOI
33 Siang, J., Lim, M.H., and Leong M.S., "Review of VibrationBased Energy Harvesting Technology: Mechanism and Architectural Approach," International Journal of Energy Research, Vol. 42, No. 5, 2018, pp. 1866-1893.   DOI
34 Mokhtari, F., Spinks, G.M., Sayyar, S., Cheng, Z., Ruhparwar, A., and Foroughi, J., "Highly Stretchable Self-Powered Wearable Electrical Energy Generator and Sensors," Advanced Materials Technologies, Vol. 6, No. 2, 2021, 2000841.   DOI
35 Shin, S.H., Kim, Y.H., Lee, M.H., Jung, J.Y., and Nah, J.H., "Hemispherically Aggregated BaTiO3 Nanoparticle Composite Thin Film for High-Performance Flexible Piezoelectric Nanogenerator," ACS Nano, Vol. 8, No. 3, 2014, pp. 2766-2773.   DOI
36 Kim, J.H., Loh, K.J., and Lynch, J.P., "Piezoelectric Polymeric Thin Films Tuned by Carbon Nanotube Fillers," Proceedings of the Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems, San Diego, California, USA, Apr. 2008, 693232.
37 Pusty, M., Sharma, A., Sinha, L., Chaudhary, A., and Shirage, P., "Comparative Study with a Unique Arrangement to Tap Piezoelectric Output to Realize a Self-poled PVDF Based Nanocomposite for Energy Harvesting Applications," Chemistry Select, Vol. 2, No. 9, 2017, pp. 2774-2782.
38 Rajabi, A.H., Jaffe, M., and Arinzeh, T.L., "Piezoelectric Materials for Tissue Regeneration: A Review," Acta Biomaterialia, Vol. 24, 2015, pp. 12-23.   DOI
39 Ryndzionek, R., Sienkiewicz, L., Michna, M., and Kutt, F., "Design and Experiments of a Piezoelectric Motor Using Three Rotating Mode Actuators," Sensors, Vol. 19, 2019, 5184.   DOI
40 Katzir, S., The Beginnings of Piezoelectricity, Springer Pub. Co., New York, USA, 2006.
41 Manbachi, A., and Cobbold, R.S.C., "Development and Application of Piezoelectric Materials for Ultrasound Generation and Detection," Ultrasound, Vol. 19, 2011, pp. 187-196.   DOI
42 Patra, A., Pal, A., and Sen, S., "Polyvinylpyrrolidone Modified Barium Zirconate Titanate/Polyvinylidene Fluoride Nanocomposites as Self-Powered Sensor," Ceramics International, Vol. 44, No. 10, 2018, pp. 11196-11203.   DOI
43 Alameh, A.H., Gratuze, M., and Nabki, F., "Impact of Geometry on the Performance of Cantilever-Based Piezoelectric Vibration Energy Harvesters," IEEE Sensors Journal, Vol. 19, No. 22, 2019, pp. 10316-10326.   DOI
44 Anjana, J., Prashanth, K.J., Asheesh, K.S., Arpit, J., and Rashmi, P.N., "Dielectric and Piezoelectric Properties of PVDF/PZT Composites: A Review," Polymer Engineering and Science, Vol. 55, No. 7, 2015, pp. 1589-1616.   DOI
45 Coondoo, I., Panwar, N., Amorin, H., Alguero, M., and Kholkin, A.L., "Synthesis and Characterization of Lead-Free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 Ceramic," Journal of Applied Physics, Vol. 113, 2013, 214107.   DOI
46 Grewe, M.G., Gururaja, T.R., Shrout, T.R., and Newnham, R.E., "Acoustic Properties of Particle/Polymer Composites for Ultrasonic Transducer Backing Applications," IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 37, No. 6, 1990, pp. 506-514.   DOI
47 Sinha, N., Goel, S., Joseph, A.J., Yadav, H., Batra, K., Gupta, M.K., and Kumar, B., "Y-Doped ZnO Nanosheets: Gigantic Piezoelectric Response for an Ultra-Sensitive Flexible Piezoelectric Nanogenerator," Ceramics International, Vol. 44, No. 7, 2018, pp. 8582-8590.   DOI
48 Tian, S., and Wang, X., "Fabrication and Performances of Epoxy/Multi-Walled Carbon Nanotubes/Piezoelectric Ceramic Composites as Rigid Piezo-Damping Materials," Journal of Materials Science, Vol. 43, 2008, pp. 4979-4987.   DOI
49 Fu, J., Hou, Y., Gao, X., Zheng, M., and Zhu, M., "Highly Durable Piezoelectric Energy Harvester Based on a PVDF Flexible Nanocomposite Filled with Oriented BaTi2O5 Nanorods with High Power Density," Nano Energy, Vol. 52, 2018, pp. 391-401.   DOI
50 Gao, X., Zheng, M., Yan, X., Fu, J., Zhu, M., and Hou, Y., "The Alignment of BCZT Particles in PDMS Boosts the Sensitivity and Cycling Reliability of a Flexible Piezoelectric Touch Sensor," Journal of Materials Chemistry C, Vol. 7, 2019, pp. 961-967.   DOI
51 McCall, W.R., Kim, K.G., Heath, C., Pierre, G.L., and Sirbuly, D.J., "Piezoelectric Nanoparticle-Polymer Composite Foams," ACS Applied Materials & Interfaces, Vol. 6, No. 22, 2014, pp. 19504-19509.   DOI
52 Izyumskaya, N., Alivov, Y.I., Cho, S.J., Morkoc., Lee, H., and Kang, Y.S., "Processing, Structure, Properties, and Applications of PZT Thin Films," Critical Reviews in Solid State and Materials Sciences, Vol. 32, No. 3-4, 2007, pp. 111-202.   DOI
53 Kim, M.J., Wu, Y.S., Kan, E.C., and Fan, J., "Breathable and Flexible Piezoelectric ZnO@PVDF Fibrous Nanogenerator for Wearable Applications," Polymers, Vol. 10, No. 7, 2018, 745.   DOI
54 Dudem, B., Kim, D.H., Bharat, L.K., and Yu, J.S., "Highly-Flexible Piezoelectric Nanogenerators with Silver Nanowires and Barium Titanate Embedded Composite Films for Mechanical Energy Harvesting," Applied Energy, Vol. 230, 2018, pp. 865-874.   DOI
55 Lee, H.J., Zhang, S., Bar-Cohen, Y., and Sherrit, S.T., "High Temperature, High Power Piezoelectric Composite Transducers," Sensors, Vol. 14, 2014, pp. 14526-14552.   DOI
56 Acosta, M., Novak, N., Rojas, V., Patel, S., Vaish, R., Koruza, J., Rossetti Jr, G.A., and Rodel, J., "BaTiO3-Based Piezoelectrics: Fundamentals, Current Status, and Perspectives," Applied Physics Reviews, Vol. 4, 2017, 041305.   DOI
57 Shin, S.H., Kwon, Y.H., Lee, M.H., Jung, J.Y., Seol, J.H., and Nah, J.H., "A Vanadium-Doped ZnO Nanosheets-Polymer Composite for Flexible Piezoelectric Nanogenerators," Nanoscale, Vol. 8, No. 3, 2016, pp. 1314-1321.   DOI
58 Vivekananthan, V., Alluri, N.R., Chandrasekhar, A., Purusothaman, Y., Gupta, A., and Kim, S.J., "Zero-Power Consuming Intruder Identification System by Enhanced Piezoelectricity of K0.5Na0.5NbO3 Using Substitutional Doping of BTO NPs," Journal of Materials Chemistry C, Vol. 7, No. 25, 2019, pp. 7563-7571.   DOI
59 Peng, Y., Peng, Q., and Liu, S., "Preparation of Barium Titanate Nanopowder through Thermal Decomposition of Peroxide Precursor and Its Formation Mechanism," Chinese Journal of Chemistry, Vol. 27, No. 11, 2009, pp. 2291-2295.   DOI
60 Han, W., He, H., Zhang, L., Dong, C., Zeng, H., Dai, Y., Xing, L., Zhang, Y., and Xue, X., "A Self-Powered Wearable Noninvasive Electronic-Skin for Perspiration Analysis Based on Piezo-Biosensing Unit Matrix of Enzyme/ZnO Nanoarrays," ACS Applied Materials & Interfaces, Vol. 9, No. 35, 2017, pp. 29526-29537.   DOI
61 Liu, H., Zhong, J., Lee, C.K., Lee, S.W., and Lin, L., "A Comprehensive Review on Piezoelectric Energy Harvesting Technology: Materials, Mechanisms, and Applications," Applied Physics Reviews, Vol. 5, 2018, 041306.   DOI
62 Li, Z., Zhang, X., and Li, G., "In Situ ZnO Nanowire Growth to Promote the PVDF Piezo Phase and the ZnO-PVDF Hybrid Self-Rectified Nanogenerator as a Touch Sensor," Physical Chemistry Chemical Physics, Vol. 16, No. 12, 2014, pp. 5475-5479.   DOI
63 Parangusan, H., Ponnamma, D., and Al-Maadeed, M.A.A., "Stretchable Electrospun PVDF-HFP/Co-ZnO Nanofibers as Piezoelectric Nanogenerators," Scientific Reports, Vol. 8, 2018, 754.   DOI
64 Newnham, R.E., Bowen, L.J., Klicker, K.A., and Cross, L.E., "Composite Piezoelectric Transducers," Materials & Design, Vol. 2, No. 2, 1980, pp. 93-106.   DOI
65 Zhen, Y., and Li, J.F., "Preparation and Electrical Properties of Fine-Scale 1-3 Lead Zirconic Titanate/Epoxy Composite Thick Films for High-Frequency Ultrasonic Transducers," Journal of Applied Physics, Vol. 103, 2008, 084119.   DOI
66 Skinner, D.P., Newnham, R.E., and Cross, L.E., "Flexible Composite Transducers," Materials Research Bulletin, Vol. 13, No. 6, 1978, pp. 599-607.   DOI
67 Guan, X., Zhang, Y., Li, H., and Ou, J., "PZT/PVDF Composites Doped with Carbon Nanotubes," Sensors and Actuators A: Physical, Vol. 194, 2013, pp. 228-231.   DOI
68 Kim, H.J., and Kim, Y.J., "High Performance Flexible Piezoelectric Pressure Sensor Based on CNTs-Doped 0-3 CeramicEpoxy Nanocomposites," Materials & Design, Vol. 151, 2018, pp. 133-140.   DOI
69 Adhikari, S., Friswell, M.I., and Inman, D.J., "Piezoelectric Energy Harvesting from Broadband Random Vibrations," Smart Materials and Structures, Vol. 18, No. 11, 2009, 115005.   DOI
70 Parangusan, H., Ponnamma, D., and Al-Maadeed, M.A.A., "Flexible Tri-Layer Piezoelectric Nanogenerator Based on PVDF-HFP/Ni-Doped ZnO Nanocomposites," RCS Advances, Vol. 7, No. 79, 2017, pp. 50156-50165.
71 Lin, Z., Yang, Y., Wu, J.M., Liu, Y., Zhang, F., and Wang, Z.L., "BaTiO3 Nanotubes-Based Flexible and Transparent Nanogenerators," The Journal of Physical Chemistry Letters, Vol. 3, No. 23, 2012, pp. 3599-3604.   DOI
72 Yaqoob, U., and Chung, G.S., "Effect of Reduced Graphene Oxide on the Energy Harvesting Performance of P(VDF-TrFE)-BaTiO3 Nanocomposite Devices," Smart Materials and Structures, Vol. 26, No. 9, 2017, 095060.   DOI
73 Klicker, K.A., Biggers, J.V., and Newnham, R.E., "Composites of PZT and Epoxy for Transducer Applications," Journal of the American Ceramic Society, Vol. 64, No. 1, 1981, pp. 5-9.   DOI
74 Li, F., and Zuo, R., "Bismuth Sodium Titanate Based Lead-Free Ceramic/Epoxy 1-3 Composites: Fabrication and Electromechanical Properties," Journal of Materials Science: Materials in Electronics, Vol. 25, 2014, pp. 2730-2736.   DOI
75 Han, K.H., and Roh, Y.R., "The Performance of a 1-3 Mode Piezocomposite Ultrasonic Transducer in Relation to the Properties of Its Polymer Matrix," Sensors and Actuators, Vol. 75, 1999, pp. 176-185.   DOI
76 Alluri, N.R., Chandrasekhar, A., Vivekananthan, V., Purusothaman, Y., Selvarajan, S., Jeong, J.H., and Kim, S.J., "Scavenging Biomechanical Energy Using High-Performance, Flexible BaTiO3 Nanocube/PDMS Composite Films," ACS Sustainable Chemistry & Engineering, Vol. 5, No. 6, 2017, pp. 4730-4738.   DOI
77 Lee, T.I., Jang, W.S., Lee, E.K., Kim, Y.S., Wang, Z.L., Baik, H.K., and Myoung, J.M., "Ultrathin Self-Powered Artificial Skin," Energy & Environmental Science, Vol. 7, No. 12, 2014, pp. 3994-3999.   DOI
78 Ngoc, H.V., and Kang, D.J., "Flexible, Transparent and Exceptionally High Power Output Nanogenerators Based on Ultrathin ZnO Nanoflakes," Nanoscale, Vol. 8, No. 9, 2016, pp. 5059-5066.   DOI
79 Xia, M., Luo, C., Su, X., Li, Y., Li, P., Hu, J., Li, G., Jiang, H., and Zhang, W., "KNN/PDMS/C-Based Lead-Free Piezoelectric Composite Film for Flexible Nanogenerator," Journal of Materials Science: Materials in Electronics, Vol. 30, 2019, pp. 7558-7566.   DOI
80 Augustine, R., Dan, P., Sosnik, A., Kalarikkal, N., Tran, N., Vincent, B., Thomas, S., Menu, P., and Rouxel, D., "Electrospun Poly(vinylidene fluoride-trifluoroethylene)/Zinc Oxide Nanocomposite Tissue Engineering Scaffolds with Enhanced Cell Adhesion and Blood Vessel Formation," Nano Research, Vol. 10, 2017, pp. 3358-3376.   DOI
81 Lim, S.M., Son, D.H., Kim, J.M., Lee, Y.B., Song, J.K., Choi, S.J., Lee, D.J., Kim, J.H., Lee, M.B., Hyeon, T.H., and Kim, D.H., "Transparent and Stretchable Interactive Human Machine Interface Based on Patterned Graphene Heterostructures," Advanced Functional Materials, Vol. 25, No. 3, 2015, pp.375-383.   DOI
82 Chorsi, M.T., Curry, E.J., Chorsi, H.T., Das, R., Baroody, J., Purohit, P.K., Ilies, H., and Nguyen, T.D., "Piezoelectric Biomaterials for Sensors and Actuators," Advanced Materials, Vol. 31, No. 1, 2019, 1802084.   DOI
83 Zhu, G., Zeng, Z., Zhang, L., and Yan, X., "Piezoelectricity in β-Phase PVDF Crystals: A Molecular Simulation Study," Computational Materials Science, Vol. 44, No. 2, 2008, pp. 224-229.   DOI
84 Hwang, J.O., Lee, D.H., Kim, J.Y., Han, T.H., Kim, B.H., Park, M.K., No, K.S., and Kim, S.O., "Vertical ZnO Nanowires/Graphene Hybrids for Transparent and Flexible Field Emission," Journal of Materials Chemistry, Vol. 21, No. 11, 2011, pp. 3432-3437.   DOI
85 Park, K.I., Lee, M.B., Liu, Y., Moon, S., Hwang, G.T., Zhu, G., Kim, J.E., Kim, S.O., Kim, D.K., Wang, Z.L., and Lee, K.J., "Flexible Nanocomposite Generator Made of BaTiO3 Nanoparticles and Graphitic Carbons," Advanced Materials, Vol. 24, No. 22, 2012, pp. 2999-3004.   DOI
86 Yan, J., and Jeong, Y.G., "Roles of Carbon Nanotube and BaTiO3 Nanofiber in the Electrical, Dielectric and Piezoelectric Properties of Flexible Nanocomposite Generators," Composites Science and Technology, Vol. 144, 2017, pp. 1-10.   DOI
87 Wang, Z.L., and Song, J., "Piezoelectric Nanogenerators Based on Zinc Oxide Nanowire Arrays," Science, Vol. 312, No. 5771, 2006, pp. 242-246.   DOI
88 Mason, W.P., "Piezoelectricity, Its History and Applications," The Journal of the Acoustical Society of America, Vol. 70, 1981, 1561.   DOI
89 Bairagi, S., and Ali, S.W., "A Hybrid Piezoelectric Nanogenerator Comprising of KNN/ZnO Nanorods Incorporated PVDF Electrospun Nanocomposite Webs," Energy Research, Vol. 44, No. 2, 2020, pp. 5545-5563.   DOI
90 Jiang, X., Kuklin, A.V., Baev, A., Ge, Y., Agren, H., Zhang, H., and Prasad, P.N., "Two-Dimensional MXenes: From Morphological to Optical, Electric, and Magnetic Properties and Applications," Physics Reports, Vol. 848, 2020, pp. 1-58.   DOI
91 Wang, S., Wang, Z.L., and Yang, Y., "A One-Structure-Based Hybridized Nanogenerator for Scavenging Mechanical and Thermal Energies by Triboelectric-Piezoelectric-Pyroelectric Effects," Advanced Materials, Vol. 28, No. 15, 2016, pp. 2881-2887.   DOI
92 Izadgoshasb, I., Lim, Y.Y., Lake, N., Tang, L., Padilla, R.V., and Kashiwao, T., "Optimizing Orientation of Piezoelectric Cantilever Beam for Harvesting Energy From Human Walking," Energy Conversion and Management, Vol. 161, 2018, pp. 66-73.   DOI
93 Jin, C., Hao, N., Xu, Z., Trase, I., Nie, Y., Dong, L., Closson, A., Chen, Z., and Zhang, J.X.J., "Flexible Piezoelectric Nanogenerators Using Metal-Doped ZnO-PVDF Films," Sensors and Actuators A: Physical, Vol. 305, 2020, 111912.   DOI
94 Mokhtari, F., Spinks, G.M., Fay, C., Cheng, Z., Raad, R., Xi, J., and Foroughi, J., "Wearable Electronic Textiles from Nanostructured Piezoelectric Fibers," Advanced Materials Technologies, Vol. 5, No. 4, 2020, 1900900.   DOI
95 Pal, A., Sasmal, A., Manoj, B., Rao, DSD.P., Haldar, A.K., and Sen, S., "Enhancement in Energy Storage and Piezoelectric Performance of Three Phase (PZT/MWCNT/PVDF) Composite," Materials Chemistry and Physics, Vol. 244, 2020, 122639.   DOI