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López-Díaz A, Vázquez AS, Vázquez E. Hydrogels in Soft Robotics: Past, Present, and Future. ACS NANO 2024; 18:20817-20826. [PMID: 39099317 PMCID: PMC11328171 DOI: 10.1021/acsnano.3c12200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/06/2024]
Abstract
The rise of soft robotics in recent years has motivated significant developments in smart materials (and vice versa), as these materials allow for more compact robotic designs thanks to the embodied intelligence that they provide. Hydrogels have long been postulated as one of the potential candidates to be used in soft robotics due to their softness, elasticity, and smart properties that can be tuned with nanomaterials. However, nowadays they represent only a small percentage of the materials used in the field. In this perspective, the drawbacks that have hindered their utilization so far are analyzed as well as the current state of hydrogel-based soft actuators, sensors, and manufacturing possibilities. The future improvements that need to be made to achieve a real application of hydrogels in soft robotics are also discussed.
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Affiliation(s)
- Antonio López-Díaz
- Escuela Técnica Superior de Ingeniería Industrial, Universidad de Castilla-La Mancha, 13071, Ciudad Real, Spain
| | - Andrés S Vázquez
- Escuela Técnica Superior de Ingeniería Industrial, Universidad de Castilla-La Mancha, 13071, Ciudad Real, Spain
| | - Ester Vázquez
- Instituto Regional de Investigación Científica Aplicada, Universidad de Castilla-La Mancha, 13071, Ciudad Real, Spain
- Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-La Mancha, 13071, Ciudad Real, Spain
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Linul P, Bănică R, Grad O, Linul E, Vaszilcsin N. Highly Electroconductive Metal-Polymer Hybrid Foams Based on Silver Nanowires: Manufacturing and Characterization. Polymers (Basel) 2024; 16:608. [PMID: 38475292 DOI: 10.3390/polym16050608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 02/12/2024] [Accepted: 02/19/2024] [Indexed: 03/14/2024] Open
Abstract
Due to their electroconductive properties, flexible open-cell polyurethane foam/silver nanowire (PUF/AgNW) structures can provide an alternative for the construction of cheap pressure transducers with limited lifetimes or used as filter media for air conditioning units, presenting bactericidal and antifungal properties. In this paper, highly electroconductive metal-polymer hybrid foams (MPHFs) based on AgNWs were manufactured and characterized. The electrical resistance of MPHFs with various degrees of AgNW coating was measured during repeated compression. For low degrees of AgNW coating, the decrease in electrical resistance during compression occurs in steps and is not reproducible with repeated compression cycles due to the reduced number of electroconductive zones involved in obtaining electrical conductivity. For high AgNW coating degrees, the decrease in resistance is quasi-linear and reproducible after the first compression cycle. However, after compression, cracks appear in the foam cell structure, which increases the electrical resistance and decreases the mechanical strength. It can be considered that PUFs coated with AgNWs have a compression memory effect and can be used as cheap solutions in industrial processes in which high precision is not required, such as exceeding a maximum admissible load or as ohmic seals for product security.
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Affiliation(s)
- Petrică Linul
- Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Piata Victoriei 2, 300 006 Timisoara, Romania
| | - Radu Bănică
- National Institute for Research and Development in Electrochemistry and Condensed Matter, Dr. A. Paunescu Podeanu Street, No. 144, 300 569 Timisoara, Romania
| | - Oana Grad
- Research Institute for Renewable Energy, Politehnica University Timisoara, 138 Gavril Musicescu, 300 501 Timisoara, Romania
| | - Emanoil Linul
- Department of Mechanics and Strength of Materials, Politehnica University Timisoara, 1 Mihai Viteazu Avenue, 300 222 Timisoara, Romania
| | - Nicolae Vaszilcsin
- Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Piata Victoriei 2, 300 006 Timisoara, Romania
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Li J, Ding Q, Wang H, Wu Z, Gui X, Li C, Hu N, Tao K, Wu J. Engineering Smart Composite Hydrogels for Wearable Disease Monitoring. NANO-MICRO LETTERS 2023; 15:105. [PMID: 37060483 PMCID: PMC10105367 DOI: 10.1007/s40820-023-01079-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 03/16/2023] [Indexed: 05/31/2023]
Abstract
Growing health awareness triggers the public's concern about health problems. People want a timely and comprehensive picture of their condition without frequent trips to the hospital for costly and cumbersome general check-ups. The wearable technique provides a continuous measurement method for health monitoring by tracking a person's physiological data and analyzing it locally or remotely. During the health monitoring process, different kinds of sensors convert physiological signals into electrical or optical signals that can be recorded and transmitted, consequently playing a crucial role in wearable techniques. Wearable application scenarios usually require sensors to possess excellent flexibility and stretchability. Thus, designing flexible and stretchable sensors with reliable performance is the key to wearable technology. Smart composite hydrogels, which have tunable electrical properties, mechanical properties, biocompatibility, and multi-stimulus sensitivity, are one of the best sensitive materials for wearable health monitoring. This review summarizes the common synthetic and performance optimization strategies of smart composite hydrogels and focuses on the current application of smart composite hydrogels in the field of wearable health monitoring.
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Affiliation(s)
- Jianye Li
- State Key Laboratory of Optoelectronic Materials and Technologies and the Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Qiongling Ding
- State Key Laboratory of Optoelectronic Materials and Technologies and the Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Hao Wang
- State Key Laboratory of Optoelectronic Materials and Technologies and the Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Zixuan Wu
- State Key Laboratory of Optoelectronic Materials and Technologies and the Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Xuchun Gui
- State Key Laboratory of Optoelectronic Materials and Technologies and the Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Chunwei Li
- Department of Otolaryngology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Ning Hu
- Department of Chemistry, Zhejiang University, Hangzhou, 310058, People's Republic of China.
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou, 311215, People's Republic of China.
| | - Kai Tao
- Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China.
| | - Jin Wu
- State Key Laboratory of Optoelectronic Materials and Technologies and the Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China.
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Yu K, He T. Silver-Nanowire-Based Elastic Conductors: Preparation Processes and Substrate Adhesion. Polymers (Basel) 2023; 15:polym15061545. [PMID: 36987325 PMCID: PMC10058989 DOI: 10.3390/polym15061545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 03/14/2023] [Accepted: 03/15/2023] [Indexed: 03/30/2023] Open
Abstract
The production of flexible electronic systems includes stretchable electrical interconnections and flexible electronic components, promoting the research and development of flexible conductors and stretchable conductive materials with large bending deformation or torsion resistance. Silver nanowires have the advantages of high conductivity, good transparency and flexibility in the development of flexible electronic products. In order to further prepare system-level flexible systems (such as autonomous full-software robots, etc.), it is necessary to focus on the conductivity of the system's composite conductor and the robustness of the system at the physical level. In terms of conductor preparation processes and substrate adhesion strategies, the more commonly used solutions are selected. Four kinds of elastic preparation processes (pretensioned/geometrically topological matrix, conductive fiber, aerogel composite, mixed percolation dopant) and five kinds of processes (coating, embedding, changing surface energy, chemical bond and force, adjusting tension and diffusion) to enhance the adhesion of composite conductors using silver nanowires as current-carrying channel substrates were reviewed. It is recommended to use the preparation process of mixed percolation doping and the adhesion mode of embedding/chemical bonding under non-special conditions. Developments in 3D printing and soft robots are also discussed.
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Affiliation(s)
- Kai Yu
- College of Mechanical and Electrical Engineering, Qingdao University, Qingdao 266071, China
| | - Tian He
- College of Mechanical and Electrical Engineering, Qingdao University, Qingdao 266071, China
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Kim H, Kwon G, Park C, You J, Park W. Anti-Counterfeiting Tags Using Flexible Substrate with Gradient Micropatterning of Silver Nanowires. MICROMACHINES 2022; 13:168. [PMID: 35208293 PMCID: PMC8878480 DOI: 10.3390/mi13020168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/18/2022] [Accepted: 01/20/2022] [Indexed: 01/25/2023]
Abstract
Anti-counterfeiting technologies for small products are being developed. We present an anti-counterfeiting tag, a grayscale pattern of silver nanowires (AgNWs) on a flexible substrate. The anti-counterfeiting tag that is observable with a thermal imaging camera was fabricated using the characteristics of silver nanowires with high visible light transmittance and high infrared emissivity. AgNWs were patterned at microscale via a maskless lithography method using UV dicing tape with UV patterns. By attaching and detaching an AgNW coated glass slide and UV dicing tape irradiated with multiple levels of UV, we obtained AgNW patterns with four or more grayscales. Peel tests confirmed that the adhesive strength of the UV dicing tape varied according to the amount of UV irradiation, and electrical resistance and IR image intensity measurements confirmed that the pattern obtained using this tape has multi-level AgNW concentrations. When applied for anti-counterfeiting, the gradient-concentration AgNW micropattern could contain more information than a single-concentration micropattern. In addition, the gradient AgNW micropattern could be transferred to a flexible polymer substrate using a simple method and then attached to various surfaces for use as an anti-counterfeiting tag.
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Affiliation(s)
- Hyeli Kim
- Department of Electronic Engineering, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea;
- Institute for Wearable Convergence Electronics, Department of Electronics and Information Convergence Engineering, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea
| | - Goomin Kwon
- Department of Plant & Environmental New Resources, Graduate School of Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea;
| | - Cheolheon Park
- Bio-MAX Institute, Seoul National University, Seoul 08826, Korea;
| | - Jungmok You
- Department of Plant & Environmental New Resources, Graduate School of Biotechnology, Institute of Life Science and Resources, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea;
| | - Wook Park
- Department of Electronic Engineering, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea;
- Institute for Wearable Convergence Electronics, Department of Electronics and Information Convergence Engineering, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea
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Abstract
Skin-like electronics are developing rapidly to realize a variety of applications such as wearable sensing and soft robotics. Hydrogels, as soft biomaterials, have been studied intensively for skin-like electronic utilities due to their unique features such as softness, wetness, biocompatibility and ionic sensing capability. These features could potentially blur the gap between soft biological systems and hard artificial machines. However, the development of skin-like hydrogel devices is still in its infancy and faces challenges including limited functionality, low ambient stability, poor surface adhesion, and relatively high power consumption (as ionic sensors). This review aims to summarize current development of skin-inspired hydrogel devices to address these challenges. We first conduct an overview of hydrogels and existing strategies to increase their toughness and conductivity. Next, we describe current approaches to leverage hydrogel devices with advanced merits including anti-dehydration, anti-freezing, and adhesion. Thereafter, we highlight state-of-the-art skin-like hydrogel devices for applications including wearable electronics, soft robotics, and energy harvesting. Finally, we conclude and outline the future trends.
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Affiliation(s)
- Binbin Ying
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King’s College Road, Toronto, ON M5S 3G8, Canada
- Department of Mechanical Engineering, McGill University, 817 Sherbrooke Street West, Montreal, QC H3A 0C3, Canada
| | - Xinyu Liu
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King’s College Road, Toronto, ON M5S 3G8, Canada
- Institute of Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9, Canada
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Shih DF, Wang JL, Chao SC, Chen YF, Liu KS, Chiang YS, Wang C, Chang MY, Yeh SL, Chu PH, Lai CS, Shye DC, Ho LH, Yang CM. Flexible Textile-Based Pressure Sensing System Applied in the Operating Room for Pressure Injury Monitoring of Cardiac Operation Patients. SENSORS (BASEL, SWITZERLAND) 2020; 20:E4619. [PMID: 32824481 PMCID: PMC7472060 DOI: 10.3390/s20164619] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/06/2020] [Accepted: 08/14/2020] [Indexed: 02/02/2023]
Abstract
Pressure injury is the most important issue facing paralysis patients and the elderly, especially in long-term care or nursing. A new interfacial pressure sensing system combined with a flexible textile-based pressure sensor array and a real-time readout system improved by the Kalman filter is proposed to monitor interfacial pressure progress in the cardiac operation. With the design of the Kalman filter and parameter optimization, noise immunity can be improved by approximately 72%. Additionally, cardiac operation patients were selected to test this developed system for the direct correlation between pressure injury and interfacial pressure for the first time. The pressure progress of the operation time was recorded and presented with the visible data by time- and 2-dimension-dependent characteristics. In the data for 47 cardiac operation patients, an extreme body mass index (BMI) and significantly increased pressure after 2 h are the top 2 factors associated with the occurrence of pressure injury. This methodology can be used to prevent high interfacial pressure in high-risk patients before and during operation. It can be suggested that this system, integrated with air mattresses, can improve the quality of care and reduce the burden of the workforce and medical cost, especially for pressure injury.
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Affiliation(s)
- De-Fen Shih
- eBio Technology Inc., Xinzhuang, New Taipei City 242, Taiwan; (D.-F.S.); (J.-L.W.); (S.-C.C.); (D.-C.S.)
| | - Jyh-Liang Wang
- eBio Technology Inc., Xinzhuang, New Taipei City 242, Taiwan; (D.-F.S.); (J.-L.W.); (S.-C.C.); (D.-C.S.)
- Department of Electronic Engineering, Ming Chi University of Technology, New Taipei 243, Taiwan
| | - Sou-Chih Chao
- eBio Technology Inc., Xinzhuang, New Taipei City 242, Taiwan; (D.-F.S.); (J.-L.W.); (S.-C.C.); (D.-C.S.)
- Department of Electronic Engineering, Ming Chi University of Technology, New Taipei 243, Taiwan
| | - Yin-Fa Chen
- Institute of Electro-Optical Engineering, Chang Gung University, Taoyuan 333, Taiwan; (Y.-F.C.); (C.-M.Y.)
| | - Kuo-Sheng Liu
- Department of Cardiac Surgery, Chang Gung Memorial Hospital, Linkou 333, Taiwan;
| | - Yi-Shan Chiang
- Department of Nursing, Linkou Chang Gung Memorial Hospital, Linkou 333, Taiwan; (Y.-S.C.); (C.W.); (M.-Y.C.); (S.-L.Y.)
| | - Chi Wang
- Department of Nursing, Linkou Chang Gung Memorial Hospital, Linkou 333, Taiwan; (Y.-S.C.); (C.W.); (M.-Y.C.); (S.-L.Y.)
- Department of Nursing, Chang Gung University, Taoyuan 333, Taiwan
| | - Min-Yu Chang
- Department of Nursing, Linkou Chang Gung Memorial Hospital, Linkou 333, Taiwan; (Y.-S.C.); (C.W.); (M.-Y.C.); (S.-L.Y.)
- Department of Nursing, Oriental Institute of Technology, New Taipei City 220, Taiwan
| | - Shu-Ling Yeh
- Department of Nursing, Linkou Chang Gung Memorial Hospital, Linkou 333, Taiwan; (Y.-S.C.); (C.W.); (M.-Y.C.); (S.-L.Y.)
- Department of Nursing, Chang Gung University of Science and Technology, Taoyuan 333, Taiwan
| | - Pao-Hsien Chu
- Department of Cardiology, Chang Gung Memorial Hospital, School of Medicine, Chang Gung University, 199 Tung Hwa North Road, Taipei 105, Taiwan;
| | - Chao-Sung Lai
- Department of Electronic Engineering, Chang-Gung University, Taoyuan 333, Taiwan;
- Biosensor Group, Biomedical Engineering Research Center, Chang Gung University, Taoyuan 333, Taiwan
- Department of Nephrology, Chang Gung Memorial Hospital, Linkou 333, Taiwan
- Department of Materials Engineering, Ming-Chi University of Technology, New Taipei City 243, Taiwan
| | - Der-Chi Shye
- eBio Technology Inc., Xinzhuang, New Taipei City 242, Taiwan; (D.-F.S.); (J.-L.W.); (S.-C.C.); (D.-C.S.)
- Department of Electronic Engineering, Ming Chi University of Technology, New Taipei 243, Taiwan
| | - Lun-Hui Ho
- Department of Nursing, Linkou Chang Gung Memorial Hospital, Linkou 333, Taiwan; (Y.-S.C.); (C.W.); (M.-Y.C.); (S.-L.Y.)
- Department of Nursing, Chang Gung University of Science and Technology, Taoyuan 333, Taiwan
| | - Chia-Ming Yang
- Institute of Electro-Optical Engineering, Chang Gung University, Taoyuan 333, Taiwan; (Y.-F.C.); (C.-M.Y.)
- Department of Electronic Engineering, Chang-Gung University, Taoyuan 333, Taiwan;
- Biosensor Group, Biomedical Engineering Research Center, Chang Gung University, Taoyuan 333, Taiwan
- Department of General Surgery, Chang Gung Memorial Hospital, Linkou 333, Taiwan
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Jung J, Cho H, Yuksel R, Kim D, Lee H, Kwon J, Lee P, Yeo J, Hong S, Unalan HE, Han S, Ko SH. Stretchable/flexible silver nanowire Electrodes for energy device applications. NANOSCALE 2019; 11:20356-20378. [PMID: 31403636 DOI: 10.1039/c9nr04193a] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Research on sustainable and high-efficiency energy devices has recently emerged as an important global issue. These devices are now moving beyond the form of a bulk, rigid platform to a portable, flexible/stretchable format that is easily available in our daily lives. Similar to the development of an active layer for the production of next-generation energy devices, the fabrication of flexible/stretchable electrodes for the easy flow of electrons is also very important. Silver nanowire electrodes have high electronic conductivity even in a flexible/stretchable state due to their high aspect ratio and percolation network structures compared to conventional electrodes. Herein, we summarize the research in the field of flexible/stretchable electronics on energy devices fabricated using silver nanowires as the electrodes. Additionally, for a systematic presentation of the current research trends, this review classifies the surveyed research efforts into the categories of energy production, storage, and consumption.
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Affiliation(s)
- Jinwook Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Hyunmin Cho
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea and Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Recep Yuksel
- Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS) Ulsan, 44919, Republic of Korea
| | - Dongkwan Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Habeom Lee
- School of Mechanical Engineering, Pusan National University, 2 Busandaehag-ro, 63Beon-gil, Geumjeong-gu, Busan, 46241, Republic of Korea
| | - Jinhyeong Kwon
- Manufacturing System R&BD Group, Korea Institute of Industrial Technology (KITECH), 89 Yangdaegiro-gil, Ipjang-myon, Seobuk-gu, Cheonan, Chungcheongnam-do 31056, Republic of Korea
| | - Phillip Lee
- Photoelectronic Hybrid Research Center, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea
| | - Junyeob Yeo
- Novel Applied Nano Optics Lab, Department of Physics, Kyungpook National University, 80 Daehak-ro, Pookgu, Daegu 41566, Republic of Korea
| | - Sukjoon Hong
- Department of Mechanical Engineering, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Husnu Emrah Unalan
- Department of Metallurgical and Materials Engineering, Middle East Technical University, Ankara 06800, Turkey
| | - Seungyong Han
- Multiscale Bio-inspired Technology Lab, Department of Mechanical Engineering, Ajou University, 206 World cup-ro, Yeongtong-gu, Suwon, Gyeonggi-do 16499, Republic of Korea.
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea and Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea and Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
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