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Nanomaterials
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Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors
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Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors

A special issue of Nanomaterials (ISSN 2079-4991). This special issue belongs to the section "Nanoelectronics, Nanosensors and Devices".

Deadline for manuscript submissions: closed (31 August 2022) | Viewed by 43177

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editors

Dr. Qiongfeng Shi

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Guest Editor
NUS Lab of Sensors, MEMS and NEMS for Internet of Things (IoT) Applications, National University of Singapore, Singapore 117583, Singapore
Interests: energy harvesting; self-powered electronics; wearable electronics; MEMS; sensors
Special Issues, Collections and Topics in MDPI journals
Dr. Jianxiong Zhu

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Guest Editor
School of Mechanical Engineering, Southeast University, Nanjing 211189, China
Interests: human interface sensor; self-powered sensor; wearable sensor; digital twin; data confusion
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

With the rapid development of the information industry and 5G networks, self-sustained devices and systems could dramatically benefit from energy-harvesting technologies (piezoelectric, triboelectric, electromagnetic, thermoelectric, pyroelectric, photovoltaic, etc.). In the past few years, energy-harvesting technologies have received significant research efforts from numerous research groups across the world, leading to in-depth innovation and rapid advancement in the field. Other than the development into energy harvesters and power sources, energy-harvesting technologies can also be adopted to develop diversified self-powered devices, ranging from physical sensors, chemical sensors, and IoT sensor nodes, all the way to functional interfaces, actuators, etc. Enabled by the innovative energy harvesters and self-powered devices, self-sustained and functional systems could eventually be realized, rendering a large variety of promising applications in the new era, such as smart homes, sports training, health care, medical rehabilitation, robotics, entertainment, and machine-learning-assisted intelligent systems for greater convenience of human life.

This Special Issue seeks to showcase research papers and review articles in this field and welcomes contributions devoted to the design, fabrication, characterization, integration, and application of energy harvesters, nanogenerators, and self-powered sensors and systems, with particular interest in flexible, wearable, and implantable technologies; human–machine interface; IoT; machine learning; big data; and other applications.

Dr. Qiongfeng Shi
Dr. Jianxiong Zhu
Guest Editors

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Nanomaterials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2900 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Energy harvesters
  • Piezoelectric nanogenerator
  • Triboelectric nanogenerator
  • Pyroelectric nanogenerator
  • Thermoelectric generator
  • Electromagnetic generator
  • Power management
  • Self-powered sensors
  • Self-powered systems

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Related Special Issue

Published Papers (11 papers)

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Editorial

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3 pages, 191 KiB  
Editorial
Special Issue: Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors
by Qiongfeng Shi and Jianxiong Zhu
Nanomaterials 2022, 12(18), 3167; https://doi.org/10.3390/nano12183167 - 13 Sep 2022
Cited by 2 | Viewed by 1325
Abstract
Internet of things (IoT) technologies are greatly promoted by the rapidly developed 5G-and-beyond networks, which have spawned diversified applications in the new era including smart homes, digital health, sports training, robotics, human–machine interaction, metaverse, smart manufacturing and industry 4 [...] Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)

Research

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16 pages, 6073 KiB  
Article
Temperature-Dependent Self-Powered Solar-Blind Photodetector Based on Ag2O/β-Ga2O3 Heterojunction
by Taejun Park, Sangbin Park, Joon Hui Park, Ji Young Min, Yusup Jung, Sinsu Kyoung, Tai Young Kang, Kyunghwan Kim, You Seung Rim and Jeongsoo Hong
Nanomaterials 2022, 12(17), 2983; https://doi.org/10.3390/nano12172983 - 29 Aug 2022
Cited by 14 | Viewed by 2612
Abstract
In this study, a high-photoresponsivity self-powered deep ultraviolet (DUV) photodetector based on an Ag2O/β-Ga2O3 heterojunction was fabricated by depositing a p-type Ag2O thin film onto an n-type β-Ga2O3 layer. The device characteristics after [...] Read more.
In this study, a high-photoresponsivity self-powered deep ultraviolet (DUV) photodetector based on an Ag2O/β-Ga2O3 heterojunction was fabricated by depositing a p-type Ag2O thin film onto an n-type β-Ga2O3 layer. The device characteristics after post-annealing at temperatures ranging from 0 to 400 °C were investigated. Our DUV devices exhibited typical rectification characteristics. At a post-annealing temperature of 300 °C, the as-fabricated device had a low leakage current of 4.24 × 10−11 A, ideality factor of 2.08, and a barrier height of 1.12 eV. Moreover, a high photo-responsivity of 12.87 mA/W was obtained at a 100 μW/cm2 light intensity at a 254 nm wavelength at zero bias voltage, the detectivity was 2.70 × 1011 Jones, and the rise and fall time were 29.76, 46.73 ms, respectively. Based on these results, the Ag2O/β-Ga2O3 heterojunction photodetector operates without an externally applied voltage and has high responsivity, which will help in the performance improvement of ultraviolet sensing systems. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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9 pages, 1513 KiB  
Article
Self-Powered Resistance-Switching Properties of Pr0.7Ca0.3MnO3 Film Driven by Triboelectric Nanogenerator
by Yanzi Huang, Lingyu Wan, Jiang Jiang, Liuyan Li and Junyi Zhai
Nanomaterials 2022, 12(13), 2199; https://doi.org/10.3390/nano12132199 - 27 Jun 2022
Cited by 4 | Viewed by 3506
Abstract
As one of the promising non-volatile memories (NVMs), resistive random access memory (RRAM) has attracted extensive attention. Conventional RRAM is deeply dependent on external power to induce resistance-switching, which restricts its applications. In this work, we have developed a self-powered RRAM that consists [...] Read more.
As one of the promising non-volatile memories (NVMs), resistive random access memory (RRAM) has attracted extensive attention. Conventional RRAM is deeply dependent on external power to induce resistance-switching, which restricts its applications. In this work, we have developed a self-powered RRAM that consists of a Pr0.7Ca0.3MnO3 (PCMO) film and a triboelectric nanogenerator (TENG). With a traditional power supply, the resistance switch ratio achieves the highest switching ratio reported so far, 9 × 107. By converting the mechanical energy harvested by a TENG into electrical energy to power the PCMO film, we demonstrate self-powered resistance-switching induced by mechanical movement. The prepared PCMO shows excellent performance of resistance switching driven by the TENG, and the resistance switch ratio is up to 2 × 105, which is higher than the ones ever reported. In addition, it can monitor real-time mechanical changes and has a good response to the electrical signals of different waveforms. This self-powered resistance switching can be induced by random movements based on the TENG. It has potential applications in the fields of self-powered sensors and human-machine interaction. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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13 pages, 18422 KiB  
Article
A Non-Resonant Piezoelectric–Electromagnetic–Triboelectric Hybrid Energy Harvester for Low-Frequency Human Motions
by Gang Tang, Zhen Wang, Xin Hu, Shaojie Wu, Bin Xu, Zhibiao Li, Xiaoxiao Yan, Fang Xu, Dandan Yuan, Peisheng Li, Qiongfeng Shi and Chengkuo Lee
Nanomaterials 2022, 12(7), 1168; https://doi.org/10.3390/nano12071168 - 31 Mar 2022
Cited by 18 | Viewed by 3090
Abstract
With the rapid development of wireless communication and micro-power technologies, smart wearable devices with various functionalities appear more and more in our daily lives. Nevertheless, they normally possess short battery life and need to be recharged with external power sources with a long [...] Read more.
With the rapid development of wireless communication and micro-power technologies, smart wearable devices with various functionalities appear more and more in our daily lives. Nevertheless, they normally possess short battery life and need to be recharged with external power sources with a long charging time, which seriously affects the user experience. To help extend the battery life or even replace it, a non-resonant piezoelectric–electromagnetic–triboelectric hybrid energy harvester is presented to effectively harvest energy from low-frequency human motions. In the designed structure, a moving magnet is used to simultaneously excite the three integrated energy collection units (i.e., piezoelectric, electromagnetic, and triboelectric) with a synergistic effect, such that the overall output power and energy-harvesting efficiency of the hybrid device can be greatly improved under various excitations. The experimental results show that with a vibration frequency of 4 Hz and a displacement of 200 mm, the hybrid energy harvester obtains a maximum output power of 26.17 mW at 70 kΩ for one piezoelectric generator (PEG) unit, 87.1 mW at 500 Ω for one electromagnetic generator (EMG) unit, and 63 μW at 140 MΩ for one triboelectric nanogenerator (TENG) unit, respectively. Then, the generated outputs are adopted for capacitor charging, which reveals that the performance of the three-unit integration is remarkably stronger than that of individual units. Finally, the practical energy-harvesting experiments conducted on various body parts such as wrist, calf, hand, and waist indicate that the proposed hybrid energy harvester has promising application potential in constructing a self-powered wearable system as the sustainable power source. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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14 pages, 6144 KiB  
Article
Physical Operations of a Self-Powered IZTO/β-Ga2O3 Schottky Barrier Diode Photodetector
by Madani Labed, Hojoong Kim, Joon Hui Park, Mohamed Labed, Afak Meftah, Nouredine Sengouga and You Seung Rim
Nanomaterials 2022, 12(7), 1061; https://doi.org/10.3390/nano12071061 - 24 Mar 2022
Cited by 6 | Viewed by 2800
Abstract
In this work, a self-powered, solar-blind photodetector, based on InZnSnO (IZTO) as a Schottky contact, was deposited on the top of Si-doped β-Ga2O3 by the sputtering of two-faced targets with InSnO (ITO) as an ohmic contact. A detailed numerical simulation [...] Read more.
In this work, a self-powered, solar-blind photodetector, based on InZnSnO (IZTO) as a Schottky contact, was deposited on the top of Si-doped β-Ga2O3 by the sputtering of two-faced targets with InSnO (ITO) as an ohmic contact. A detailed numerical simulation was performed by using the measured J–V characteristics of IZTO/β-Ga2O3 Schottky barrier diodes (SBDs) in the dark. Good agreement between the simulation and the measurement was achieved by studying the effect of the IZTO workfunction, β-Ga2O3 interfacial layer (IL) electron affinity, and the concentrations of interfacial traps. The IZTO/β-Ga2O3 (SBDs) was tested at a wavelength of 255 nm with the photo power density of 1 mW/cm2. A high photo-to-dark current ratio of 3.70×105 and a photoresponsivity of 0.64 mA/W were obtained at 0 V as self-powered operation. Finally, with increasing power density the photocurrent increased, and a 17.80 mA/W responsivity under 10 mW/cm2 was obtained. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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12 pages, 4282 KiB  
Article
An Energy Harvester Coupled with a Triboelectric Mechanism and Electrostatic Mechanism for Biomechanical Energy Harvesting
by Lei Zhai, Lingxiao Gao, Ziying Wang, Kejie Dai, Shuai Wu and Xiaojing Mu
Nanomaterials 2022, 12(6), 933; https://doi.org/10.3390/nano12060933 - 11 Mar 2022
Cited by 15 | Viewed by 2540
Abstract
Energy-harvesting devices based on a single energy conversion mechanism generally have a low output and low conversion efficiency. To solve this problem, an energy harvester coupled with a triboelectric mechanism and electrostatic mechanism for biomechanical energy harvesting is presented. The output performances of [...] Read more.
Energy-harvesting devices based on a single energy conversion mechanism generally have a low output and low conversion efficiency. To solve this problem, an energy harvester coupled with a triboelectric mechanism and electrostatic mechanism for biomechanical energy harvesting is presented. The output performances of the device coupled with a triboelectric mechanism and electrostatic mechanism were systematically studied through principle analysis, simulation, and experimental demonstration. Experiments showed that the output performance of the device was greatly improved by coupling the electrostatic induction mechanisms, and a sustainable and enhanced peak power of approximately 289 μW was produced when the external impedance was 100 MΩ, which gave over a 46-fold enhancement to the conventional single triboelectric conversion mechanism. Moreover, it showed higher resolution for motion states compared with the conventional triboelectric nanogenerator, and can precisely and constantly monitor and distinguish various motion states, including stepping, walking, running, and jumping. Furthermore, it can charge a capacitor of 10 μF to 3 V within 2 min and light up 16 LEDs. On this basis, a self-powered access control system, based on gait recognition, was successfully demonstrated. This work proposes a novel and cost-effective method for biomechanical energy harvesting, which provides a more convenient choice for human motion status monitoring and can be widely used in personnel identification systems. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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10 pages, 2062 KiB  
Article
A Light-Driven Integrated Bio-Capacitor with Single Nano-Channel Modulation
by Jie Lin, Yu-Jia Lv, Lei Han, Kuan Sun, Yan Xiang, Xiao-Xing Xing and Yu-Tao Li
Nanomaterials 2022, 12(4), 592; https://doi.org/10.3390/nano12040592 - 9 Feb 2022
Cited by 4 | Viewed by 2437
Abstract
Bioelectronics, an emerging discipline formed by the biology and electronic information disciplines, has maintained a state of rapid development since its birth. Amongst the various functional bioelectronics materials, bacteriorhodopsin (bR), with its directional proton pump function and favorable structural stability properties, has drawn [...] Read more.
Bioelectronics, an emerging discipline formed by the biology and electronic information disciplines, has maintained a state of rapid development since its birth. Amongst the various functional bioelectronics materials, bacteriorhodopsin (bR), with its directional proton pump function and favorable structural stability properties, has drawn wide attention. The main contents of the paper are as follows: Inspired by the capacitive properties of natural protoplast cell membranes, a new bio-capacitor based on bR and artificial nanochannels was constructed. As a point of innovation, microfluidic chips were integrated into our device as an ion transport channel, which made the bio-capacitor more stable. Meanwhile, a single nanopore structure was integrated to improve the accuracy of the device structure. Experiments observed that the size of the nanopore affected the ion transmission rate. Consequently, by making the single nanopore’s size change, the photocurrent duration time (PDT) of bR was effectively regulated. By using this specific phenomenon, the original transient photocurrent was successfully transformed into a square-like wave. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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Review

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24 pages, 2918 KiB  
Review
Recent Progress on Triboelectric Nanogenerators for Vibration Energy Harvesting and Vibration Sensing
by Ahmed Haroun, Mohamed Tarek, Mohamed Mosleh and Farouk Ismail
Nanomaterials 2022, 12(17), 2960; https://doi.org/10.3390/nano12172960 - 26 Aug 2022
Cited by 50 | Viewed by 6191
Abstract
The triboelectric nanogenerator (TENG) is a recent technology that reforms kinetic energy generation and motion sensing. A TENG comes with variety of structures and mechanisms that make it suitable for wide range of applications and working conditions. Since mechanical vibrations are abundant source [...] Read more.
The triboelectric nanogenerator (TENG) is a recent technology that reforms kinetic energy generation and motion sensing. A TENG comes with variety of structures and mechanisms that make it suitable for wide range of applications and working conditions. Since mechanical vibrations are abundant source of energy in the surrounding environment, the development of a TENG for vibration energy harvesting and vibration measurements has attracted a huge attention and great research interest through the past two decades. Due to the high output voltage and high-power density of a TENG, it can be used as a sustainable power supply for small electronics, smart devices, and wireless sensors. In addition, it can work as a vibration sensor with high sensitivity. This article reviews the recent progress in the development of a TENG for vibration energy harvesting and vibration measurements. Systems of only a TENG or a hybrid TENG with other transduction technologies, such as piezoelectric and electromagnetic, can be utilized for vibrations scavenging. Vibration measurement can be done by measuring either vibration displacement or vibration acceleration. Each can provide full information about the vibration amplitude and frequency. Some TENG vibration-sensing architectures may also be used for energy harvesting due to their large output power. Numerous applications can rely on TENG vibration sensors such as machine condition monitoring, structure health monitoring, and the Internet of things (IoT). Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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31 pages, 9494 KiB  
Review
Recent Progress of Nanogenerators for Green Energy Harvesting: Performance, Applications, and Challenges
by Enrique Delgado-Alvarado, Ernesto A. Elvira-Hernández, José Hernández-Hernández, Jesús Huerta-Chua, Héctor Vázquez-Leal, Jaime Martínez-Castillo, Pedro J. García-Ramírez and Agustín L. Herrera-May
Nanomaterials 2022, 12(15), 2549; https://doi.org/10.3390/nano12152549 - 25 Jul 2022
Cited by 29 | Viewed by 5395
Abstract
Natural sources of green energy include sunshine, water, biomass, geothermal heat, and wind. These energies are alternate forms of electrical energy that do not rely on fossil fuels. Green energy is environmentally benign, as it avoids the generation of greenhouse gases and pollutants. [...] Read more.
Natural sources of green energy include sunshine, water, biomass, geothermal heat, and wind. These energies are alternate forms of electrical energy that do not rely on fossil fuels. Green energy is environmentally benign, as it avoids the generation of greenhouse gases and pollutants. Various systems and equipment have been utilized to gather natural energy. However, most technologies need a huge amount of infrastructure and expensive equipment in order to power electronic gadgets, smart sensors, and wearable devices. Nanogenerators have recently emerged as an alternative technique for collecting energy from both natural and artificial sources, with significant benefits such as light weight, low-cost production, simple operation, easy signal processing, and low-cost materials. These nanogenerators might power electronic components and wearable devices used in a variety of applications such as telecommunications, the medical sector, the military and automotive industries, and internet of things (IoT) devices. We describe new research on the performance of nanogenerators employing several green energy acquisition processes such as piezoelectric, electromagnetic, thermoelectric, and triboelectric. Furthermore, the materials, applications, challenges, and future prospects of several nanogenerators are discussed. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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31 pages, 7175 KiB  
Review
Advanced Implantable Biomedical Devices Enabled by Triboelectric Nanogenerators
by Chan Wang, Qiongfeng Shi and Chengkuo Lee
Nanomaterials 2022, 12(8), 1366; https://doi.org/10.3390/nano12081366 - 15 Apr 2022
Cited by 44 | Viewed by 7393
Abstract
Implantable biomedical devices (IMDs) play essential roles in healthcare. Subject to the limited battery life, IMDs cannot achieve long-term in situ monitoring, diagnosis, and treatment. The proposal and rapid development of triboelectric nanogenerators free IMDs from the shackles of batteries and spawn a [...] Read more.
Implantable biomedical devices (IMDs) play essential roles in healthcare. Subject to the limited battery life, IMDs cannot achieve long-term in situ monitoring, diagnosis, and treatment. The proposal and rapid development of triboelectric nanogenerators free IMDs from the shackles of batteries and spawn a self-powered healthcare system. This review aims to overview the development of IMDs based on triboelectric nanogenerators, divided into self-powered biosensors, in vivo energy harvesting devices, and direct electrical stimulation therapy devices. Meanwhile, future challenges and opportunities are discussed according to the development requirements of current-level self-powered IMDs to enhance output performance, develop advanced triboelectric nanogenerators with multifunctional materials, and self-driven close-looped diagnosis and treatment systems. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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39 pages, 9851 KiB  
Review
Advances in Electrochemical Detection Electrodes for As(III)
by Haibing Hu, Baozhu Xie, Yangtian Lu and Jianxiong Zhu
Nanomaterials 2022, 12(5), 781; https://doi.org/10.3390/nano12050781 - 25 Feb 2022
Cited by 29 | Viewed by 4298
Abstract
Arsenic is extremely abundant in the Earth’s crust and is one of the most common environmental pollutants in nature. In the natural water environment and surface soil, arsenic exists mainly in the form of trivalent arsenite (As(III)) and pentavalent arsenate (As(V)) ions, and [...] Read more.
Arsenic is extremely abundant in the Earth’s crust and is one of the most common environmental pollutants in nature. In the natural water environment and surface soil, arsenic exists mainly in the form of trivalent arsenite (As(III)) and pentavalent arsenate (As(V)) ions, and its toxicity can be a serious threat to human health. In order to manage the increasingly serious arsenic pollution in the living environment and maintain a healthy and beautiful ecosystem for human beings, it is urgent to conduct research on an efficient sensing method suitable for the detection of As(III) ions. Electrochemical sensing has the advantages of simple instrumentation, high sensitivity, good selectivity, portability, and the ability to be analyzed on site. This paper reviews various electrode systems developed in recent years based on nanomaterials such as noble metals, bimetals, other metals and their compounds, carbon nano, and biomolecules, with a focus on electrodes modified with noble metal and metal compound nanomaterials, and evaluates their performance for the detection of arsenic. They have great potential for achieving the rapid detection of arsenic due to their excellent sensitivity and strong interference immunity. In addition, this paper discusses the relatively rare application of silicon and its compounds as well as novel polymers in achieving arsenic detection, which provides new ideas for investigating novel nanomaterial sensing. We hope that this review will further advance the research progress of high-performance arsenic sensors based on novel nanomaterials. Full article
(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors)
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