Roadmap on energy harvesting materials

Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere

Polyaniline Nanostructures Embedded Ethylcellulose Conductive Polymer Composite Films-Based Triboelectric Nanogenerators for Mechanical Energy Harvesting and Self-Powered Electronics

The fast growth of wearable/portable electronics and the demand for highly effective and long-lasting self-powered systems to support their off-grid operation have significantly increased. Triboelectric nanogenerators (TENGs), a promising energy-harvesting technology, have attracted research interest in recent years for wearable and self-powered portable electronic applications. In this report, conductive polyaniline (PANI) nanostructures (NSs) were synthesized via a facile chemical oxidation polymerization method. The synthesized PANI NSs were embedded into a triboelectric ethylcellulose (EC) polymer to form a conductive polymer composite film (PANI/EC-CPCF), which enhances the triboelectricity and electrical conductivity of the CPCF. The prepared PANI/EC-CPCF layer and commercially available fluorinated ethylene propylene were employed as positive and negative triboelectric materials, which are used to construct a TENG device. The output electrical performance of the fabricated TENGs was studied and optimized systematically by varying the filler amount of PANI NSs in the EC polymer. The optimized TENG exhibited high output voltage, current, charge density, and power density values of ∼130 V, ∼5 μA, ∼45 μC/m2, and ∼650 mW/m2, respectively. Furthermore, the robustness analysis and mechanical stability of the TENG were studied under a long-term durability test for several days. Finally, the practical and real-time applications of the proposed TENG were demonstrated by varying the environmental conditions and harvesting mechanical energy from daily human actions in a living environment, which is used to power several low-power electronic gadgets

Polyaniline Nanostructures Embedded Ethylcellulose Conductive Polymer Composite Films-Based Triboelectric Nanogenerators for Mechanical Energy Harvesting and Self-Powered Electronics

The fast growth of wearable/portable electronics and the demand for highly effective and long-lasting self-powered systems to support their off-grid operation have significantly increased. Triboelectric nanogenerators (TENGs), a promising energy-harvesting technology, have attracted research interest in recent years for wearable and self-powered portable electronic applications. In this report, conductive polyaniline (PANI) nanostructures (NSs) were synthesized via a facile chemical oxidation polymerization method. The synthesized PANI NSs were embedded into a triboelectric ethylcellulose (EC) polymer to form a conductive polymer composite film (PANI/EC-CPCF), which enhances the triboelectricity and electrical conductivity of the CPCF. The prepared PANI/EC-CPCF layer and commercially available fluorinated ethylene propylene were employed as positive and negative triboelectric materials, which are used to construct a TENG device. The output electrical performance of the fabricated TENGs was studied and optimized systematically by varying the filler amount of PANI NSs in the EC polymer. The optimized TENG exhibited high output voltage, current, charge density, and power density values of ∼130 V, ∼5 μA, ∼45 μC/m2, and ∼650 mW/m2, respectively. Furthermore, the robustness analysis and mechanical stability of the TENG were studied under a long-term durability test for several days. Finally, the practical and real-time applications of the proposed TENG were demonstrated by varying the environmental conditions and harvesting mechanical energy from daily human actions in a living environment, which is used to power several low-power electronic gadgets

Natural silk-composite enabled versatile robust triboelectric nanogenerators for smart applications

Strategies to maximize the surface charge density across triboelectric layers while protecting it from humidity are crucial in employing triboelectric nanogenerators (TENGs) for commercial/real-time applications. Herein, for the first time, we propose the utility of crystalline silk microparticles (SMPs) to improve the surface charge density in materials like polyvinyl alcohol to realise its applicability for TENG devices. Moreover, these SMPs are extracted from discarded Bombyx mori silkworm cocoons by facile, inexpensive, and single-step alkaline-hydrolysis treatment. We examine the performance of these composites with counter-materials composed of waste PTFE plastic cups to show reuse in recycled products. The processing cost of TENG developed from recycled materials is not only low but eco-friendly. The TENG performance as a function of the concentration of SMPs is investigated and compared with the composite's work-function and surface-potentials, with the distance-dependent electric field theoretical model employed to optimize the performance. Consequently, the optimized TENG exhibits maximum output voltage, current, charge, and power density of ∼280 V, 17.3 μA, 32.5 nC, and 14.4 W·m−2, respectively, creating a highly competitive energy harvester that can conform to the rigorous needs of wearables and mobile applications. Furthermore, the fully packaged silicone rubber device protects it from humidity and enables the device utility for practical applications with a soft, comfortable, and skin-friendly interface

Polyaniline Nanostructures Embedded Ethylcellulose Conductive Polymer Composite Films-Based Triboelectric Nanogenerators for Mechanical Energy Harvesting and Self-Powered Electronics

The fast growth of wearable/portable electronics and the demand for highly effective and long-lasting self-powered systems to support their off-grid operation have significantly increased. Triboelectric nanogenerators (TENGs), a promising energy-harvesting technology, have attracted research interest in recent years for wearable and self-powered portable electronic applications. In this report, conductive polyaniline (PANI) nanostructures (NSs) were synthesized via a facile chemical oxidation polymerization method. The synthesized PANI NSs were embedded into a triboelectric ethylcellulose (EC) polymer to form a conductive polymer composite film (PANI/EC-CPCF), which enhances the triboelectricity and electrical conductivity of the CPCF. The prepared PANI/EC-CPCF layer and commercially available fluorinated ethylene propylene were employed as positive and negative triboelectric materials, which are used to construct a TENG device. The output electrical performance of the fabricated TENGs was studied and optimized systematically by varying the filler amount of PANI NSs in the EC polymer. The optimized TENG exhibited high output voltage, current, charge density, and power density values of ∼130 V, ∼5 μA, ∼45 μC/m2, and ∼650 mW/m2, respectively. Furthermore, the robustness analysis and mechanical stability of the TENG were studied under a long-term durability test for several days. Finally, the practical and real-time applications of the proposed TENG were demonstrated by varying the environmental conditions and harvesting mechanical energy from daily human actions in a living environment, which is used to power several low-power electronic gadgets

Natural silk-composite enabled versatile robust triboelectric nanogenerators for smart applications

Strategies to maximize the surface charge density across triboelectric layers while protecting it from humidity are crucial in employing triboelectric nanogenerators (TENGs) for commercial/real-time applications. Herein, for the first time, we propose the utility of crystalline silk microparticles (SMPs) to improve the surface charge density in materials like polyvinyl alcohol to realise its applicability for TENG devices. Moreover, these SMPs are extracted from discarded Bombyx mori silkworm cocoons by facile, inexpensive, and single-step alkaline-hydrolysis treatment. We examine the performance of these composites with counter-materials composed of waste PTFE plastic cups to show reuse in recycled products. The processing cost of TENG developed from recycled materials is not only low but eco-friendly. The TENG performance as a function of the concentration of SMPs is investigated and compared with the composite's work-function and surface-potentials, with the distance-dependent electric field theoretical model employed to optimize the performance. Consequently, the optimized TENG exhibits maximum output voltage, current, charge, and power density of ∼280 V, 17.3 μA, 32.5 nC, and 14.4 W·m−2, respectively, creating a highly competitive energy harvester that can conform to the rigorous needs of wearables and mobile applications. Furthermore, the fully packaged silicone rubber device protects it from humidity and enables the device utility for practical applications with a soft, comfortable, and skin-friendly interface

Exploring the theoretical and experimental optimization of high-performance triboelectric nanogenerators using microarchitectured silk cocoon films

Triboelectric nanogenerators (TENGs) developed using eco-friendly natural materials instead of traditional electronic materials are more favorable for biocompatible applications, as well as from a sustainable life-cycle analysis perspective. Microarchitectured silkworm fibroin films with high surface roughness and an outstanding ability to lose electrons are used to design TENGs. An alcohol-annealing treatment is utilized to strengthen the resistance of the silk film (SF) against humidity and aqueous solubility. Herein, for the first time, the distance-dependent electric field theoretical model is employed to optimize the TENG parameters to achieve high output, which shows excellent agreement with the experimental outputs of SF-based TENG. The alcohol-treated microarchitectured SF (AT-MASF) with a polytetrafluoroethylene positive contact exhibits a stable and high electrical output even in harsh environments. These studies can lead us closer to the attractive future vision of realizing biodegradable TENG systems for harness/sensing various biomechanical activities even under real/humid environments. The potential and real-time application of the proposed AT-MASF-based TENG is demonstrated by directly employing its electric power to drive a number of low-power portable electronics and for sensing in human-body centric activities

Exploring the theoretical and experimental optimization of high-performance triboelectric nanogenerators using microarchitectured silk cocoon films

Triboelectric nanogenerators (TENGs) developed using eco-friendly natural materials instead of traditional electronic materials are more favorable for biocompatible applications, as well as from a sustainable life-cycle analysis perspective. Microarchitectured silkworm fibroin films with high surface roughness and an outstanding ability to lose electrons are used to design TENGs. An alcohol-annealing treatment is utilized to strengthen the resistance of the silk film (SF) against humidity and aqueous solubility. Herein, for the first time, the distance-dependent electric field theoretical model is employed to optimize the TENG parameters to achieve high output, which shows excellent agreement with the experimental outputs of SF-based TENG. The alcohol-treated microarchitectured SF (AT-MASF) with a polytetrafluoroethylene positive contact exhibits a stable and high electrical output even in harsh environments. These studies can lead us closer to the attractive future vision of realizing biodegradable TENG systems for harness/sensing various biomechanical activities even under real/humid environments. The potential and real-time application of the proposed AT-MASF-based TENG is demonstrated by directly employing its electric power to drive a number of low-power portable electronics and for sensing in human-body centric activities

Roadmap on energy harvesting materials

Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere

Roadmap on energy harvesting materials

Funder: Fundação para a Ciência e TecnologiaFunder: BIDEKO ProjectFunder: MCIN/AEIFunder: Spanish State Research Agency (AEI)Funder: Basic Science Research ProgramFunder: Ministry of Education; doi: http://dx.doi.org/10.13039/501100002701Funder: Swedish Knowledge FoundationFunder: University of Calgary; doi: http://dx.doi.org/10.13039/100008459Funder: National Renewable Energy Laboratory; doi: http://dx.doi.org/10.13039/100006233Funder: Fonds de recherche du Québec – Nature et technologies; doi: http://dx.doi.org/10.13039/501100003151Funder: Canada Research Chairs programFunder: EUFunder: National Research Foundation of Korea; doi: http://dx.doi.org/10.13039/501100003725Funder: NRFFunder: Priority Research Centers ProgramFunder: European regional development fund (ERDF)Funder: European Research Council (ERC)Funder: ERCFunder: Alliance for Sustainable Energy, LLCFunder: MIURFunder: Italian MinistryFunder: the Cardiff University, Engineering and Physical Sciences Research CouncilFunder: JST Mirai ProgramFunder: Agence Nationale de la Recherche (ANR)Funder: A*STARFunder: JSTFunder: PRESTOFunder: Aerospace ProgrammeFunder: EBFunder: U.S. Department of Commerce, National Institute of Standards and TechnologyFunder: Laboratory-Directed Research and Development (LDRD)Funder: Sandia, LLCFunder: the Office of Science, Office of Basic Energy SciencesFunder: United States GovernmentFunder: Honeywell International Inc.Funder: The Leverhulme TrustFunder: Royal Academy of Engineering; doi: http://dx.doi.org/10.13039/501100000287Funder: Office of the Chief Science Adviser for National SecurityFunder: Henry Samueli School of Engineering & Applied ScienceFunder: Department of Bioengineering at the University of California, Los AngelesFunder: CRESTFunder: Beijing Forestry University; doi: http://dx.doi.org/10.13039/501100012138Funder: Japan Science and Technology Agency (JST)Funder: the Australian Research Council, QUTFunder: Center for Hierarchical Materials DesignFunder: Austrian Christian Doppler Laboratory for ThermoelectricityFunder: HBIS-UQ Innovation Centre for Sustainable SteelAbstract Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere.</jats:p