Nanogenerators as a Sustainable Power Source: State of Art, Applications, and Challenges

A sustainable power source to meet the needs of energy requirement is very much essential in modern society as the conventional sources are depleting. Bioenergy, hydropower, solar, and wind are some of the well-established renewable energy sources that help to attain the need for energy at mega to gigawatts power scale. Nanogenerators based on nano energy are the growing technology that facilitate self-powered systems, sensors, and flexible and portable electronics in the booming era of IoT (Internet of Things). The nanogenerators can harvest small-scale energy from the ambient nature and surroundings for efficient utilization. The nanogenerators were based on piezo, tribo, and pyroelectric effect, and the first of its kind was developed in the year 2006 by Wang et al. The invention of nanogenerators is a breakthrough in the field of ambient energy-harvesting techniques as they are lightweight, easily fabricated, sustainable, and care-free systems. In this paper, a comprehensive review on fundamentals, performance, recent developments, and application of nanogenerators in self-powered sensors, wind energy harvesting, blue energy harvesting, and its integration with solar photovoltaics are discussed. Finally, the outlook and challenges in the growth of this technology are also outlined.

[1]  Zhaoling Li,et al.  Multilayered fiber-based triboelectric nanogenerator with high performance for biomechanical energy harvesting , 2018, Nano Energy.

[2]  Zhong Lin Wang,et al.  Electrostatic potential in a bent piezoelectric nanowire. The fundamental theory of nanogenerator and nanopiezotronics. , 2007, Nano letters.

[3]  Qingshen Jing,et al.  Angle-shaped triboelectric nanogenerator for harvesting environmental wind energy , 2019, Nano Energy.

[4]  Zhong Lin Wang,et al.  Engineering of efficiency limiting free carriers and an interfacial energy barrier for an enhancing piezoelectric generation , 2013 .

[5]  D. Mandal,et al.  Energy harvesting and self-powered microphone application on multifunctional inorganic-organic hybrid nanogenerator , 2019, Energy.

[6]  Zhong Lin Wang,et al.  Harvesting Broad Frequency Band Blue Energy by a Triboelectric-Electromagnetic Hybrid Nanogenerator. , 2016, ACS nano.

[7]  S. Ryu,et al.  A scalable, flexible and transparent GaN based heterojunction piezoelectric nanogenerator for bending, air-flow and vibration energy harvesting , 2018, Applied Energy.

[8]  Zhong Lin Wang,et al.  Toward large-scale energy harvesting by a nanoparticle-enhanced triboelectric nanogenerator. , 2013, Nano letters.

[9]  Zhong Lin Wang,et al.  Triboelectric nanogenerator built inside shoe insole for harvesting walking energy , 2013 .

[10]  Zhong Lin Wang,et al.  Networks of triboelectric nanogenerators for harvesting water wave energy: a potential approach toward blue energy. , 2015, ACS nano.

[11]  Weiqing Yang,et al.  3D Stack Integrated Triboelectric Nanogenerator for Harvesting Vibration Energy , 2014 .

[12]  Ning Wang,et al.  Triboelectric Nanogenerator Boosts Smart Green Tires , 2018, Advanced Functional Materials.

[13]  R. F. Gouveia,et al.  Electrostatic charging of hydrophilic particles due to water adsorption. , 2009, Journal of the American Chemical Society.

[14]  Xiaonan Wen,et al.  Fully Enclosed Triboelectric Nanogenerators for Applications in Water and Harsh Environments , 2013 .

[15]  Yadong Jiang,et al.  Fully enclosed cylindrical single-electrode-based triboelectric nanogenerator. , 2014, ACS applied materials & interfaces.

[16]  Long Lin,et al.  Replacing a Battery by a Nanogenerator with 20 V Output , 2012, Advanced materials.

[17]  Yadong Jiang,et al.  Effective anti-biofouling enabled by surface electric disturbance from water wave-driven nanogenerator. , 2019, Nano energy.

[18]  Xiujian Chou,et al.  Two-dimensional triboelectric-electromagnetic hybrid nanogenerator for wave energy harvesting , 2019, Nano Energy.

[19]  Long Lin,et al.  Nanoscale triboelectric-effect-enabled energy conversion for sustainably powering portable electronics. , 2012, Nano letters.

[20]  Kai Dong,et al.  Complementary Electromagnetic‐Triboelectric Active Sensor for Detecting Multiple Mechanical Triggering , 2018 .

[21]  Jia Zhu,et al.  Piezoelectric and pyroelectric properties of intrinsic GaN nanowires and nanotubes: Size and shape effects , 2018 .

[22]  Zhong Lin Wang,et al.  Farms of triboelectric nanogenerators for harvesting wind energy: A potential approach towards green energy , 2017 .

[23]  Xudong Wang,et al.  Chemical modification of polymer surfaces for advanced triboelectric nanogenerator development , 2016 .

[24]  Xiuhan Li,et al.  3D fiber-based hybrid nanogenerator for energy harvesting and as a self-powered pressure sensor. , 2014, ACS nano.

[25]  Daniel Champier,et al.  Thermoelectric generators: A review of applications , 2017 .

[26]  Lianmao Peng,et al.  Observation of a 2D Electron Gas and the Tuning of the Electrical Conductance of ZnO Nanowires by Controllable Surface Band‐Bending , 2009 .

[27]  Yan Zhang,et al.  Pyroelectric nanogenerators for driving wireless sensors. , 2012, Nano letters.

[28]  Ayesha Sultana,et al.  Lead-free ZnSnO3/MWCNTs-based self-poled flexible hybrid nanogenerator for piezoelectric power generation , 2015, Nanotechnology.

[29]  Zhong Lin Wang,et al.  Progress in nanogenerators for portable electronics , 2012 .

[30]  Fang Zhang,et al.  Thermoelectric nanogenerators based on single Sb-doped ZnO micro/nanobelts. , 2012, ACS nano.

[31]  S. Ryu,et al.  Transparent, Flexible Piezoelectric Nanogenerator Based on GaN Membrane Using Electrochemical Lift-Off. , 2017, ACS applied materials & interfaces.

[32]  Zhong Lin Wang,et al.  Single-electrode-based sliding triboelectric nanogenerator for self-powered displacement vector sensor system. , 2013, ACS nano.

[33]  A. Filippin,et al.  3D core-multishell piezoelectric nanogenerators , 2018, Nano Energy.

[34]  Jie Wang,et al.  Standards and figure-of-merits for quantifying the performance of triboelectric nanogenerators , 2015, Nature Communications.

[35]  Zhong Lin Wang,et al.  Direct-Current Nanogenerator Driven by Ultrasonic Waves , 2007, Science.

[36]  Zhong Lin Wang,et al.  Flexible triboelectric generator , 2012 .

[37]  Zhong Lin Wang,et al.  Piezoelectric Nanogenerators Based on Zinc Oxide Nanowire Arrays , 2006, Science.

[38]  Mireille Mouis,et al.  Ultrathin Nanogenerators as Self‐Powered/Active Skin Sensors for Tracking Eye Ball Motion , 2014 .

[39]  Jun Chen,et al.  Harmonic‐Resonator‐Based Triboelectric Nanogenerator as a Sustainable Power Source and a Self‐Powered Active Vibration Sensor , 2013, Advanced materials.

[40]  Long Lin,et al.  Fully Packaged Blue Energy Harvester by Hybridizing a Rolling Triboelectric Nanogenerator and an Electromagnetic Generator. , 2016, ACS nano.

[41]  Tao Jiang,et al.  Structural Optimization of Triboelectric Nanogenerator for Harvesting Water Wave Energy. , 2015, ACS nano.

[42]  Zhong Lin Wang,et al.  Cellular level biocompatibility and biosafety of ZnO nanowires , 2008 .

[43]  Zhong Lin Wang,et al.  Direct‐Current Triboelectric Nanogenerator Realized by Air Breakdown Induced Ionized Air Channel , 2018, Advanced Energy Materials.

[44]  Joo-Yun Jung,et al.  Lithium-doped zinc oxide nanowires-polymer composite for high performance flexible piezoelectric nanogenerator. , 2014, ACS nano.

[45]  Hyunjin Kim,et al.  Hybrid energy harvester based on nanopillar solar cells and PVDF nanogenerator , 2013, Nanotechnology.

[46]  Jens Peter Kofoed,et al.  Design Specifications for the Hanstholm WEPTOS Wave Energy Converter , 2012 .

[47]  Yury Gogotsi,et al.  Metallic MXenes: A New Family of Materials for Flexible Triboelectric Nanogenerators , 2018 .

[48]  V. Hariram,et al.  COMPUTATIONAL STUDY OF LEADING EDGE JET IMPINGEMENT COOLING WITH A CONICAL CONVERGING HOLE FOR BLADE COOLING , 2017 .

[49]  Jun Chen,et al.  Triboelectric–Pyroelectric–Piezoelectric Hybrid Cell for High‐Efficiency Energy‐Harvesting and Self‐Powered Sensing , 2015, Advanced materials.

[50]  Chang Kyu Jeong,et al.  Highly‐Efficient, Flexible Piezoelectric PZT Thin Film Nanogenerator on Plastic Substrates , 2014, Advanced materials.

[51]  Hengyu Guo,et al.  Human–Machine Interfacing Enabled by Triboelectric Nanogenerators and Tribotronics , 2018, Advanced Materials Technologies.

[52]  Yury Gogotsi,et al.  2D metal carbides and nitrides (MXenes) for energy storage , 2017 .

[53]  Yury Gogotsi,et al.  25th Anniversary Article: MXenes: A New Family of Two‐Dimensional Materials , 2014, Advanced materials.

[54]  Chaoran Deng,et al.  Self-powered versatile shoes based on hybrid nanogenerators , 2018, Nano Research.

[55]  N. White,et al.  Water-Dielectric Single Electrode Mode Triboelectric Nanogenerators for Ocean Wave Impact Energy Harvesting , 2018, Proceedings.

[56]  Guang Zhu,et al.  Converting biomechanical energy into electricity by a muscle-movement-driven nanogenerator. , 2009, Nano letters.

[57]  Sang-Jae Kim,et al.  Flexible, Hybrid Piezoelectric Film (BaTi(1-x)Zr(x)O3)/PVDF Nanogenerator as a Self-Powered Fluid Velocity Sensor. , 2015, ACS applied materials & interfaces.

[58]  Zhong Lin Wang,et al.  Functional electrical stimulation by nanogenerator with 58 V output voltage. , 2012, Nano letters.

[59]  Guoxu Liu,et al.  Triboelectric Nanogenerator Based on Biocompatible Polymer Materials , 2015 .

[60]  Zhiwei Xu,et al.  Painting a high-output triboelectric nanogenerator on paper for harvesting energy from human body motion , 2018, Nano Energy.

[61]  B. Lu,et al.  High-Performance Piezoelectric Nanogenerators with Imprinted P(VDF-TrFE)/BaTiO3 Nanocomposite Micropillars for Self-Powered Flexible Sensors. , 2017, Small.

[62]  Minbaek Lee,et al.  High pyroelectric power generation of 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 single crystal , 2014 .

[63]  Kunming Shi,et al.  Synergistic effect of graphene nanosheet and BaTiO3 nanoparticles on performance enhancement of electrospun PVDF nanofiber mat for flexible piezoelectric nanogenerators , 2018, Nano Energy.

[64]  Jing Zhu,et al.  A nanowire based triboelectric nanogenerator for harvesting water wave energy and its applications , 2017 .

[65]  Zhong Lin Wang.  Catch wave power in floating nets , 2017, Nature.

[66]  Bill J. Van Heyst,et al.  A review of the state of the science on wearable thermoelectric power generators (TEGs) and their existing challenges , 2017 .

[67]  Xue Wang,et al.  Rotation sensing and gesture control of a robot joint via triboelectric quantization sensor , 2018, Nano Energy.

[68]  Zhong Lin Wang.  Triboelectric nanogenerators as new energy technology for self-powered systems and as active mechanical and chemical sensors. , 2013, ACS nano.

[69]  Zhong Lin Wang,et al.  Vertically aligned CdSe nanowire arrays for energy harvesting and piezotronic devices. , 2012, ACS nano.

[70]  Simiao Niu,et al.  Theoretical systems of triboelectric nanogenerators , 2015 .

[71]  J. Wu,et al.  High-output current density of the triboelectric nanogenerator made from recycling rice husks , 2016 .

[72]  Guocheng Liu,et al.  Optimal geometrical design of inertial vibration DC piezoelectric nanogenerators based on obliquely aligned InN nanowire arrays. , 2017, Nanoscale.

[73]  Long Lin,et al.  Grating‐Structured Freestanding Triboelectric‐Layer Nanogenerator for Harvesting Mechanical Energy at 85% Total Conversion Efficiency , 2014, Advanced materials.

[74]  Sang‐Jae Kim,et al.  Lead-free piezoelectric nanogenerator using lightweight composite films for harnessing biomechanical energy , 2019, Composites Part B: Engineering.

[75]  Yunlong Zi,et al.  A fully-packaged ship-shaped hybrid nanogenerator for blue energy harvesting toward seawater self-desalination and self-powered positioning , 2019, Nano Energy.

[76]  Dipankar Mandal,et al.  All-Organic High-Performance Piezoelectric Nanogenerator with Multilayer Assembled Electrospun Nanofiber Mats for Self-Powered Multifunctional Sensors. , 2018, ACS applied materials & interfaces.

[77]  N.Y.A. Shammas,et al.  A comprehensive review of thermoelectric technology, micro-electrical and power generation properties , 2008, 2008 26th International Conference on Microelectronics.

[78]  Tae Yun Kim,et al.  High-performance piezoelectric nanogenerators based on chemically-reinforced composites , 2018 .

[79]  Xianlong Wei,et al.  1D Piezoelectric Material Based Nanogenerators: Methods, Materials and Property Optimization , 2018, Nanomaterials.

[80]  Chi Zhang,et al.  An alginate film-based degradable triboelectric nanogenerator , 2018, RSC advances.

[81]  Ruomeng Yu,et al.  Electret film-enhanced triboelectric nanogenerator matrix for self-powered instantaneous tactile imaging. , 2014, ACS applied materials & interfaces.

[82]  Ying Wu,et al.  Piezoelectric diphenylalanine peptide for greatly improved flexible nanogenerators , 2018, Nano Energy.

[83]  G. Zhu,et al.  A Shape‐Adaptive Thin‐Film‐Based Approach for 50% High‐Efficiency Energy Generation Through Micro‐Grating Sliding Electrification , 2014, Advanced materials.

[84]  Jiangming Fu,et al.  Milk-based triboelectric nanogenerator on paper for harvesting energy from human body motion , 2019, Nano Energy.

[85]  S. Nahm,et al.  Sodium-potassium niobate nanorods with various crystal structures and their application to nanogenerator , 2017 .

[86]  Long Lin,et al.  Pyroelectric nanogenerators for harvesting thermoelectric energy. , 2012, Nano letters.

[87]  M. Willander,et al.  An Ultrathin Flexible Single‐Electrode Triboelectric‐Nanogenerator for Mechanical Energy Harvesting and Instantaneous Force Sensing , 2017 .

[88]  Xiujian Chou,et al.  An electrostatic discharge based needle-to-needle booster for dramatic performance enhancement of triboelectric nanogenerators , 2018, Applied Energy.

[89]  Weiqing Yang,et al.  Harvesting broadband kinetic impact energy from mechanical triggering/vibration and water waves. , 2014, ACS nano.

[90]  S. Beeby,et al.  Energy harvesting vibration sources for microsystems applications , 2006 .

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

[92]  Yunlong Zi,et al.  A Water‐Proof Triboelectric–Electromagnetic Hybrid Generator for Energy Harvesting in Harsh Environments , 2016 .

[93]  G. Pollack,et al.  Can water store charge? , 2009, Langmuir : the ACS journal of surfaces and colloids.

[94]  Tao Jiang,et al.  Spring-assisted triboelectric nanogenerator for efficiently harvesting water wave energy , 2017 .

[95]  Chuang Zhang,et al.  Synthesis and applications of organic nanorods, nanowires and nanotubes , 2013 .

[96]  Zhong Lin Wang.  Triboelectric nanogenerators as new energy technology and self-powered sensors - principles, problems and perspectives. , 2014, Faraday discussions.

[97]  Fernando Galembeck,et al.  Charge partitioning at gas-solid interfaces: humidity causes electricity buildup on metals. , 2010, Langmuir : the ACS journal of surfaces and colloids.

[98]  Ji-Beom Yoo,et al.  Highly Stretchable Piezoelectric‐Pyroelectric Hybrid Nanogenerator , 2014, Advanced materials.

[99]  Simiao Niu,et al.  Nanometer Resolution Self‐Powered Static and Dynamic Motion Sensor Based on Micro‐Grated Triboelectrification , 2014, Advanced materials.

[100]  Saurabh Rathore,et al.  A Critical Review on Triboelectric Nanogenerator , 2018 .

[101]  Zhong Lin Wang,et al.  Theory of contact electrification: Optical transitions in two-level systems , 2018, Nano Energy.

[102]  Tao Jiang,et al.  Stimulating Acrylic Elastomers by a Triboelectric Nanogenerator – Toward Self‐Powered Electronic Skin and Artificial Muscle , 2016 .

[103]  Long Lina,et al.  Transparent flexible nanogenerator as self-powered sensor for transportation monitoring , 2012 .

[104]  Tao Jiang,et al.  Charging System Optimization of Triboelectric Nanogenerator for Water Wave Energy Harvesting and Storage. , 2016, ACS applied materials & interfaces.

[105]  Xudong Wang,et al.  Piezoelectric nanogenerators—Harvesting ambient mechanical energy at the nanometer scale , 2012 .

[106]  Zhong‐Lin Wang,et al.  Maximized Effective Energy Output of Contact‐Separation‐Triggered Triboelectric Nanogenerators as Limited by Air Breakdown , 2017 .

[107]  Zhong Lin Wang,et al.  Theoretical study of contact-mode triboelectric nanogenerators as an effective power source , 2013 .

[108]  A Wireless Triboelectric Nanogenerator , 2017, 1707.03677.

[109]  Shutang Wang,et al.  Stretchable and Wearable Triboelectric Nanogenerator Based on Kinesio Tape for Self-Powered Human Motion Sensing , 2018, Nanomaterials.

[110]  Cheng Xu,et al.  Raising the Working Temperature of a Triboelectric Nanogenerator by Quenching Down Electron Thermionic Emission in Contact‐Electrification , 2018, Advanced materials.

[111]  Li Zheng,et al.  Silicon-based hybrid cell for harvesting solar energy and raindrop electrostatic energy , 2014 .

[112]  Daewoong Jung,et al.  Highly reliable wind-rolling triboelectric nanogenerator operating in a wide wind speed range , 2016, Scientific Reports.

[113]  Zhong Lin Wang,et al.  Water-solid surface contact electrification and its use for harvesting liquid-wave energy. , 2013, Angewandte Chemie.

[114]  Zhong Lin Wang,et al.  Enhancing the Efficiency of Silicon-Based Solar Cells by the Piezo-Phototronic Effect. , 2017, ACS nano.

[115]  Zhong Lin Wang,et al.  Triboelectric nanogenerator built on suspended 3D spiral structure as vibration and positioning sensor and wave energy harvester. , 2013, ACS nano.

[116]  Zhong-Lin Wang,et al.  Alternating the Output of a CdS Nanowire Nanogenerator by a White‐Light‐Stimulated Optoelectronic Effect , 2008 .

[117]  Dong-Weon Lee,et al.  On-vehicle triboelectric nanogenerator enabled self-powered sensor for tire pressure monitoring , 2018, Nano Energy.

[118]  Wei Liu,et al.  Theoretical study on two-dimensional MoS2 piezoelectric nanogenerators , 2016, Nano Research.

[119]  Tao Jiang,et al.  Three-dimensional ultraflexible triboelectric nanogenerator made by 3D printing , 2017, Nano Energy.

[120]  D. K. Davies,et al.  Charge generation on dielectric surfaces , 1969 .

[121]  Zhong Lin Wang,et al.  Self-powered nanowire devices. , 2010, Nature nanotechnology.

[122]  Zhong Lin Wang,et al.  Cylindrical spiral triboelectric nanogenerator , 2015, Nano Reseach.

[123]  Xi Chen,et al.  1.6 V nanogenerator for mechanical energy harvesting using PZT nanofibers. , 2010, Nano letters.

[124]  Yury Gogotsi,et al.  Nano Day: Celebrating the Next Decade of Nanoscience and Nanotechnology. , 2016, ACS nano.

[125]  Hao Yu,et al.  Enhanced Power Output of a Triboelectric Nanogenerator Composed of Electrospun Nanofiber Mats Doped with Graphene Oxide , 2015, Scientific Reports.

[126]  Yue Zhang,et al.  Influence of the carrier concentration on the piezotronic effect in a ZnO/Au Schottky junction. , 2015, Nanoscale.

[127]  F. Fan,et al.  Flexible Nanogenerators for Energy Harvesting and Self‐Powered Electronics , 2016, Advanced materials.

[128]  Zhong Lin Wang,et al.  Linear-grating triboelectric generator based on sliding electrification. , 2013, Nano letters.

[129]  G. Pollack,et al.  Where is water in the triboelectric series , 2016 .

[130]  M. AniMelfaRoji,et al.  A retrospect on the role of piezoelectric nanogenerators in the development of the green world , 2017 .

[131]  Paul S Weiss,et al.  A conversation with Prof. Zhong Lin Wang, energy harvester. , 2015, ACS nano.

[132]  Caofeng Pan,et al.  Triboelectric-generator-driven pulse electrodeposition for micropatterning. , 2012, Nano letters.

[133]  Yan Zhang,et al.  Biomolecule-adsorption-dependent piezoelectric output of ZnO nanowire nanogenerator and its application as self-powered active biosensor. , 2014, Biosensors & bioelectronics.

[134]  Shengnan Lu,et al.  Highly transparent triboelectric nanogenerator for harvesting water-related energy reinforced by antireflection coating , 2015, Scientific Reports.

[135]  Feng Zhou,et al.  Leaves based triboelectric nanogenerator (TENG) and TENG tree for wind energy harvesting , 2019, Nano Energy.

[136]  J. Brugger,et al.  All-fiber hybrid piezoelectric-enhanced triboelectric nanogenerator for wearable gesture monitoring , 2018, Nano Energy.

[137]  Long Lin,et al.  A Hybridized Power Panel to Simultaneously Generate Electricity from Sunlight, Raindrops, and Wind around the Clock , 2015 .

[138]  Zhong Lin Wang,et al.  Finger typing driven triboelectric nanogenerator and its use for instantaneously lighting up LEDs , 2013 .

[139]  Minhao Zhu,et al.  Lawn Structured Triboelectric Nanogenerators for Scavenging Sweeping Wind Energy on Rooftops , 2016, Advanced materials.

[140]  Dong Hyun Kim,et al.  Highly-flexible piezoelectric nanogenerators with silver nanowires and barium titanate embedded composite films for mechanical energy harvesting , 2018, Applied Energy.

[141]  Binoy Bera.  Recent Advances In Piezoelectric Nano generators In Energy Harvesting Applications , 2016 .

[142]  Weiqing Yang,et al.  Harvesting energy from the natural vibration of human walking. , 2013, ACS nano.

[143]  G. Sebald,et al.  Huge gain in pyroelectric energy conversion through epitaxy for integrated self-powered nanodevices , 2017 .

[144]  Zhong Lin Wang,et al.  Eye motion triggered self-powered mechnosensational communication system using triboelectric nanogenerator , 2017, Science Advances.

[145]  Ashok K. Batra,et al.  Ambient Energy Sources: Mechanical, Light, and Thermal , 2017 .

[146]  Yunlong Zi,et al.  Nanogenerators: An emerging technology towards nanoenergy , 2017 .

[147]  Tao Jiang,et al.  Multilayer wavy-structured robust triboelectric nanogenerator for harvesting water wave energy , 2016 .

[148]  Dipankar Mandal,et al.  High-performance bio-piezoelectric nanogenerator made with fish scale , 2016 .

[149]  Y. Hao,et al.  Single‐InN‐Nanowire Nanogenerator with Upto 1 V Output Voltage , 2010, Advanced materials.

[150]  Zhong Lin Wang,et al.  Triboelectric nanogenerator as self-powered active sensors for detecting liquid/gaseous water/ethanol , 2013 .

[151]  Zhong Lin Wang,et al.  Achieving ultrahigh triboelectric charge density for efficient energy harvesting , 2017, Nature Communications.

[152]  Tao Jiang,et al.  Temperature Effect on Performance of Triboelectric Nanogenerator , 2017 .

[153]  Zhong Lin Wang,et al.  Power generation with laterally packaged piezoelectric fine wires. , 2009, Nature nanotechnology.

[154]  Jun Chen,et al.  Triboelectrification-based organic film nanogenerator for acoustic energy harvesting and self-powered active acoustic sensing. , 2014, ACS nano.

[155]  Xiaogan Li,et al.  Multifunctional TENG for Blue Energy Scavenging and Self‐Powered Wind‐Speed Sensor , 2017 .

[156]  Han‐Ki Kim,et al.  Li-doped Cu2O/ZnO heterojunction for flexible and semi-transparent piezoelectric nanogenerators , 2017 .

[157]  Mr.Nikunj Adroja,et al.  Review of thermoelectricity to improve energy quality , 2015 .

[158]  Ya Yang,et al.  Enhanced self-powered UV photoresponse of ferroelectric BaTiO3 materials by pyroelectric effect , 2017 .

[159]  Dave Evans,et al.  How the Next Evolution of the Internet Is Changing Everything , 2011 .

[160]  Amir Khajepour,et al.  Piezoelectric and triboelectric nanogenerators: Trends and impacts , 2018, Nano Today.

[161]  Zhong Lin Wang,et al.  Waterproof Fabric‐Based Multifunctional Triboelectric Nanogenerator for Universally Harvesting Energy from Raindrops, Wind, and Human Motions and as Self‐Powered Sensors , 2019, Advanced science.

[162]  M. H. Raouadi,et al.  Harvesting wind energy with pyroelectric nanogenerator PNG using the vortex generator mechanism , 2018 .

[163]  Qingliang Liao,et al.  The enhanced performance of piezoelectric nanogenerator via suppressing screening effect with Au particles/ZnO nanoarrays Schottky junction , 2016, Nano Research.

[164]  Young Jae Song,et al.  Metal nanowire–polymer matrix hybrid layer for triboelectric nanogenerator , 2019, Nano Energy.

[165]  Zhong Lin Wang,et al.  Harvesting Water Drop Energy by a Sequential Contact‐Electrification and Electrostatic‐Induction Process , 2014, Advanced materials.

[166]  Muhammad Mustafa Hussain,et al.  Paper-based origami flexible and foldable thermoelectric nanogenerator , 2017 .

[167]  J. Ha,et al.  Enhanced performance of a GaN piezoelectric nanogenerator with an embedded nanoporous layer via the suppressed carrier screening effect , 2017 .

[168]  Chang Kyu Jeong,et al.  Self‐Powered Cardiac Pacemaker Enabled by Flexible Single Crystalline PMN‐PT Piezoelectric Energy Harvester , 2014, Advanced materials.

[169]  Zhong Lin Wang,et al.  Efficient Scavenging of Solar and Wind Energies in a Smart City. , 2016, ACS nano.

[170]  Weiguo Hu,et al.  Freestanding Flag-Type Triboelectric Nanogenerator for Harvesting High-Altitude Wind Energy from Arbitrary Directions. , 2016, ACS nano.

[171]  Yong Ding,et al.  Piezoelectric nanogenerator using CdS nanowires , 2008 .

[172]  Husam N. Alshareef,et al.  MXene Electrochemical Microsupercapacitor Integrated with Triboelectric Nanogenerator as a Wearable Self-charging Power Unit , 2018 .

[173]  Seonuk Park,et al.  Schottky nanocontacts on ZnO nanorod arrays , 2003 .

[174]  Tao Jiang,et al.  Butterfly‐Inspired Triboelectric Nanogenerators with Spring‐Assisted Linkage Structure for Water Wave Energy Harvesting , 2018, Advanced Materials Technologies.

[175]  Qinghua Yang,et al.  Flexible PbTiO3-nanowires/ P(VDF-TrFE) composite films and their dielectric, ferroelectric and pyroelectric properties , 2018, Ceramics International.

[176]  Jun Chen,et al.  Recent Progress in Triboelectric Nanogenerators as a Renewable and Sustainable Power Source , 2016 .

[177]  Youfan Hu,et al.  Recent progress in piezoelectric nanogenerators as a sustainable power source in self-powered systems and active sensors , 2015 .

[178]  Sang‐Woo Kim,et al.  Energy harvesting based on semiconducting piezoelectric ZnO nanostructures , 2012 .

[179]  Guang Zhu,et al.  Flexible high-output nanogenerator based on lateral ZnO nanowire array. , 2010, Nano letters.

[180]  J. Ha,et al.  Stable and High Piezoelectric Output of GaN Nanowire-Based Lead-Free Piezoelectric Nanogenerator by Suppression of Internal Screening , 2018, Nanomaterials.

[181]  Shurong Dong,et al.  Carbon electrodes enable flat surface PDMS and PA6 triboelectric nanogenerators to achieve significantly enhanced triboelectric performance , 2019, Nano Energy.

[182]  Mengmeng Liu,et al.  Self-Healable, Stretchable, Transparent Triboelectric Nanogenerators as Soft Power Sources. , 2018, ACS nano.

[183]  Zhong Lin Wang,et al.  Progress in triboelectric nanogenerators as a new energy technology and self-powered sensors , 2015 .

[184]  Simiao Niu,et al.  Triboelectric Nanogenerator Based on Fully Enclosed Rolling Spherical Structure for Harvesting Low‐Frequency Water Wave Energy , 2015 .

[185]  Zhong-Lin Wang.  Towards Self‐Powered Nanosystems: From Nanogenerators to Nanopiezotronics , 2008 .

[186]  Zhong Lin Wang,et al.  Pulsed nanogenerator with huge instantaneous output power density. , 2013, ACS nano.

[187]  B. McCarl,et al.  Economics , 1870, The Indian medical gazette.

[188]  Hao Xue,et al.  A wearable pyroelectric nanogenerator and self-powered breathing sensor , 2017 .

[189]  Y. Jung,et al.  Molecular structure engineering of dielectric fluorinated polymers for enhanced performances of triboelectric nanogenerators , 2018, Nano Energy.

[190]  Steve Dunn,et al.  Piezoelectric nanogenerators – a review of nanostructured piezoelectric energy harvesters , 2015 .

[191]  Wei Wang,et al.  r-Shaped hybrid nanogenerator with enhanced piezoelectricity. , 2013, ACS nano.

[192]  Zhong Lin Wang,et al.  Self-powered nanotech. , 2008, Scientific American.

[193]  Chen Xu,et al.  A High‐Reliability Kevlar Fiber‐ZnO Nanowires Hybrid Nanogenerator and its Application on Self‐Powered UV Detection , 2015 .

[194]  Tao Jiang,et al.  Triboelectric Nanogenerator Networks Integrated with Power Management Module for Water Wave Energy Harvesting , 2019, Advanced Functional Materials.

[195]  Long Lin,et al.  A Nanogenerator for Energy Harvesting from a Rotating Tire and its Application as a Self‐Powered Pressure/Speed Sensor , 2011, Advanced materials.

[196]  B. Cheng,et al.  Performance enhancements in poly(vinylidene fluoride)-based piezoelectric nanogenerators for efficient energy harvesting , 2019, Nano Energy.

[197]  Zhong Lin Wang,et al.  Microfibre–nanowire hybrid structure for energy scavenging , 2009, Nature.

[198]  Ki‐Hyun Kim,et al.  Piezoelectric energy harvesters for biomedical applications , 2019, Nano Energy.

[199]  Zhao Wang,et al.  Piezoelectric nanowires in energy harvesting applications , 2015 .

[200]  Tao Jiang,et al.  Toward the blue energy dream by triboelectric nanogenerator networks , 2017 .

[201]  Kyeong Nam Kim,et al.  High humidity- and contamination-resistant triboelectric nanogenerator with superhydrophobic interface , 2019, Nano Energy.

[202]  K. Lee,et al.  Reliable operation of a nanogenerator under ultraviolet light via engineering piezoelectric potential , 2013 .

[203]  Daewon Kim,et al.  Triboelectric nanogenerator with nanostructured metal surface using water-assisted oxidation , 2016 .

[204]  Xuhui Sun,et al.  Integrating a Silicon Solar Cell with a Triboelectric Nanogenerator via a Mutual Electrode for Harvesting Energy from Sunlight and Raindrops. , 2018, ACS nano.

[205]  Hyunsoo Kim,et al.  Base-treated polydimethylsiloxane surfaces as enhanced triboelectric nanogenerators , 2015 .

[206]  Soon-Gil Yoon,et al.  A comprehensive review of flexible piezoelectric generators based on organic-inorganic metal halide perovskites , 2019, Nano Energy.

[207]  Zhong Lin Wang,et al.  Simultaneously harvesting electrostatic and mechanical energies from flowing water by a hybridized triboelectric nanogenerator. , 2014, ACS nano.

[208]  Mengdi Han,et al.  Asymmetrical Triboelectric Nanogenerator with Controllable Direct Electrostatic Discharge , 2016 .

[209]  Action Nechibvute,et al.  Piezoelectric Energy Harvesting Devices: An Alternative Energy Source for Wireless Sensors , 2012 .

[210]  Peng Bai,et al.  Personalized keystroke dynamics for self-powered human--machine interfacing. , 2015, ACS nano.