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Zhao X, Tang GH. 0D/2D Co-Doping Network Enhancing Thermal Conductivity of Radiative Cooling Film for Electronic Device Thermal Management. ACS APPLIED MATERIALS & INTERFACES 2024; 16:37853-37864. [PMID: 38980937 DOI: 10.1021/acsami.4c04222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
The radiative cooling has great potential for electronic device cooling without requiring any energy consumption. However, a low thermal conductivity of most radiative cooling materials limits their application. Herein, a multishape codoping strategy was proposed to achieve collaborative enhancement of thermal conductivity and radiative properties. The hBN-coated hollow SiO2 particles were prepared based on electrostatic self-assembly technology, which were then mixed with hBN platelets and doped into a poly(vinylidene fluoride-co-hexafluoropropylene) substrate. Discrete dipole approximation theory was employed to reveal the mechanism and optimize the particle size. The results showed that the multishape codoping method can significantly improve the radiative performance, with 94.9% reflectivity and 91.2% emissivity. In addition, this zero-dimensional and two-dimensional composite doping structure facilitated the formation of a thermal conduction network, which enhanced the thermal conductivity of the film up to 1.32 W m-1 K-1. The high thermal conductivity radiative cooling film can decrease the heater temperature from 58.8 to 31.3 °C, with a further reduction of temperature by 7.2 °C compared to the radiative cooling substrates with low thermal conductivity. The net cooling power of the film can reach 102.5 W m-2 under direct sunlight. This work provides a novel strategy for high-efficiency electronic device cooling.
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Affiliation(s)
- Xin Zhao
- MOE Key Laboratory of Thermo-Fluid Science and Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - G H Tang
- MOE Key Laboratory of Thermo-Fluid Science and Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China
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2
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Ju H, Long H, Yang S, Wang F, Fang X, Fan W, Li C, Ou J, Li W. Durable Self-Cleaning Radiative Cooling Coatings for Building Energy Efficiency. ACS APPLIED MATERIALS & INTERFACES 2024; 16:32679-32692. [PMID: 38869497 DOI: 10.1021/acsami.4c04644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
Passive daytime radiative cooling (PDRC) is an energy-saving technology without an additional energy supply or environmental pollution. At present, most PDRC coatings for buildings are only aiming at high solar reflectivity (RS) and high mid-infrared emissivity (EMIR) while ignoring practicalities such as adhesion strength, scalability, and durability. In this work, modified calcined kaolin/(ethylene trifluorochloroethylene copolymer-polydimethylsiloxane) (MK/(FEVE-PDMS)) coating with super practicability is prepared by using MK as a filler, FEVE as an adhesive, and PDMS as a hydrophobic modifier. The RS and EMIR of the coating are 92.5 and 94.6%, respectively. The MK/(FEVE-PDMS) coating exhibits superhydrophobicity, with an advancing contact angle (ACA) of 160.2° and a hysteresis contact angle of 7.3°. At an average solar irradiance of 742.78 W m-2, the coating achieved a temperature drop of 13.12 °C (shielded with PE film) and 3.09 °C (without shielding), respectively, relative to the environment. The coating adheres firmly to the substrate with an adhesion strength of class 2. The superhydrophobicity of the coating provides excellent durability and ease of repair, which can resist UV aging and mechanical damage. The durable superhydrophobicity gives the coating long-term stability in PDRC performance. Additionally, the cheap raw materials and the preparation process, consistent with the production of existing paints, show excellent scalability. Moreover, the energy consumption simulation results show that the energy saving ratio of the coating is more than 10% in the densely populated Yangtze River Delta and Pearl River Delta. The durable self-cleaning radiative coating developed in this work has potential application prospects in areas where the demand for cooling in summer is large and the demand for heating in winter is small.
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Affiliation(s)
- Huiquan Ju
- School of Materials Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
| | - Haibin Long
- School of Materials Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
| | - Shasha Yang
- School of Materials Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
| | - Fajun Wang
- School of Materials Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
| | - Xinzuo Fang
- School of Chemistry and Chemical Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
| | - Wangxi Fan
- School of Chemistry and Chemical Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
| | - Changquan Li
- School of Materials Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
| | - Junfei Ou
- School of Materials Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
| | - Wen Li
- School of Materials Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China
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3
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Sun Y, Liu R, Long L, Sun Y. Preparation of a self-matting, anti-fingerprint and skin-tactile wood coating via biomimetic self-wrinkling patterns. Sci Rep 2024; 14:13275. [PMID: 38858537 PMCID: PMC11164916 DOI: 10.1038/s41598-024-64385-x] [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: 03/23/2024] [Accepted: 06/07/2024] [Indexed: 06/12/2024] Open
Abstract
Inspired by natural wrinkled surfaces, artificial surfaces with biomimetic wrinkled structures have been widely used to improve optical properties, wettability, and antibacterial properties. However, the preparation of wrinkled structures has the disadvantages of long-time consumption and complex processes. Herein, we prepared a self-wrinkling polyurethane-acrylate (PUA) wood coating via biomimetic self-wrinkling patterns by using a light-emitting diode (LED)/excimer/mercury lamp curing system, which was capable of self-matting, anti-fingerprint and skin-tactile performance. By adjusting the irradiation intensity in the curing system, the wavelength (λ) and amplitude (A) of wrinkles on the coating surface were controlled to enhance the coating performance. After curing by the LED, excimer, and mercury lamps at energy intensities of 500, 30, and 300 mW/cm2 respectively, the self-wrinkling coating showed excellent surface performance. The self-wrinkling coating represented low gloss of 4.1 GU at 85°, high hardness of 4H. Interestingly, the coating surface had a high hydrophobicity (104.5°) and low surface energy (29-30 mN/m) and low coefficient (COF) of friction (0.1-0.2), which were consistent with those of the human skin surface. Besides, the wrinkled structure also improved the thermal stability of the coating samples. This study provided a promising technique for the mass production of self-wrinkling coatings that could be used in wood-based panels, furniture, and leather.
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Affiliation(s)
- Yingchun Sun
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Ru Liu
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Ling Long
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing, 100091, China.
| | - Yuhui Sun
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing, 100091, China
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4
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Tao S, Cai W, Han J, Shi C, Fang Z, Lu C, Xu C, Li W, Xu Z. Construction of a Robust Radiative Cooling Emitter for Efficient Food Storage and Transportation. ACS APPLIED MATERIALS & INTERFACES 2024. [PMID: 38684025 DOI: 10.1021/acsami.4c02298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
Nowadays, food safety is still facing great challenges. During storage and transportation, perishable goods have to be kept at a low temperature. However, the current logistics still lack enough preservation ability to maintain a low temperature in the whole. Hence, considering the temperature fluctuation in logistics, in this work, the passive radiative cooling (RC) technology was applied to package to enhance the temperature control capability in food storage and transportation. The RC emitter with selective infrared emission property was fabricated by a facile coating method, and Al2O3 was added to improve the wear resistance. The sunlight reflectance and infrared emittance within atmospheric conditions could reach up to 0.92 and 0.84, respectively. After abrasion, the sunlight reflection only decreased by 0.01, and the infrared emission showed a negligible change, revealing excellent wear resistance. During outdoor measurement, the box assembled by RC emitters (RC box) was proved to achieve temperature drops of ∼9 and ∼4 °C compared with the corrugated box and foam box, respectively. Besides, the fruits stored in the RC box exhibited a lower decay rate. Additionally, after printing with patterns to meet the aesthetic requirements, the RC emitter could also maintain the cooling ability. Given the superior optical properties, wear resistance, and cooling capability, the emitter has great potential for obtaining a better temperature control ability in food storage and transportation.
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Affiliation(s)
- Shuang Tao
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Weikang Cai
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Jingtian Han
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Chenjie Shi
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Zhenggang Fang
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Chunhua Lu
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, P. R. China
| | - Chao Xu
- China Construction Yipin Investment and Development Co., Wuhan 430000, P. R. China
- China Construction Third Bureau Technology Innovation Industry Development Co., Wuhan 430000, P. R. China
| | - Wenjun Li
- China Construction Third Bureau Technology Innovation Industry Development Co., Wuhan 430000, P. R. China
| | - Zhongzi Xu
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, P. R. China
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5
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Liu R, Wang S, Zhou Z, Zhang K, Wang G, Chen C, Long Y. Materials in Radiative Cooling Technologies. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2401577. [PMID: 38497602 DOI: 10.1002/adma.202401577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/12/2024] [Indexed: 03/19/2024]
Abstract
Radiative cooling (RC) is a carbon-neutral cooling technology that utilizes thermal radiation to dissipate heat from the Earth's surface to the cold outer space. Research in the field of RC has garnered increasing interest from both academia and industry due to its potential to drive sustainable economic and environmental benefits to human society by reducing energy consumption and greenhouse gas emissions from conventional cooling systems. Materials innovation is the key to fully exploit the potential of RC. This review aims to elucidate the materials development with a focus on the design strategy including their intrinsic properties, structural formations, and performance improvement. The main types of RC materials, i.e., static-homogeneous, static-composite, dynamic, and multifunctional materials, are systematically overviewed. Future trends, possible challenges, and potential solutions are presented with perspectives in the concluding part, aiming to provide a roadmap for the future development of advanced RC materials.
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Affiliation(s)
- Rong Liu
- Department of Electronic Engineering, The Chinese University of Hong Kong, New Territories, Hong Kong SAR, 999077, China
| | - Shancheng Wang
- Department of Electronic Engineering, The Chinese University of Hong Kong, New Territories, Hong Kong SAR, 999077, China
| | - Zhengui Zhou
- Department of Electronic Engineering, The Chinese University of Hong Kong, New Territories, Hong Kong SAR, 999077, China
| | - Keyi Zhang
- Department of Electronic Engineering, The Chinese University of Hong Kong, New Territories, Hong Kong SAR, 999077, China
| | - Guanya Wang
- Department of Electronic Engineering, The Chinese University of Hong Kong, New Territories, Hong Kong SAR, 999077, China
| | - Changyuan Chen
- Department of Electronic Engineering, The Chinese University of Hong Kong, New Territories, Hong Kong SAR, 999077, China
| | - Yi Long
- Department of Electronic Engineering, The Chinese University of Hong Kong, New Territories, Hong Kong SAR, 999077, China
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Li L, Liu G, Zhang Q, Zhao H, Shi R, Wang C, Li Z, Zhou B, Zhang Y. Porous Structure of Polymer Films Optimized by Rationally Tuning Phase Separation for Passive All-Day Radiative Cooling. ACS APPLIED MATERIALS & INTERFACES 2024; 16:6504-6512. [PMID: 38267401 DOI: 10.1021/acsami.3c19173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
Passive all-day radiative cooling (PARC) films with porous structures prepared via nonsolvent-induced phase separation (NIPS) have attracted considerable attention owing to their cost-effectiveness and wide applicability. The PARC performances of the films correlate with their porous structures. However, the porous structure formed using the NIPS process cannot be finely regulated. In this study, we prepared polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) films with porous structures optimized by rationally tuning the phase separation, which was achieved by adjusting the proportions of two good solvents with varying solubility parameters. The optimized PVDF-HFP film with a hierarchically porous structure exhibited a high solar reflectance of 97.7% and an infrared emissivity of 96.7%. The film with excellent durability achieved an average subambient cooling temperature of approximately 5.4 °C under a solar irradiance of 945 W·m-2 as well as a temperature of 11.2 °C at nighttime, thus demonstrating all-day radiative cooling. The results indicate that the proposed films present a promising platform for large-scale applications in green building cooling and achieving carbon neutrality.
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Affiliation(s)
- Linhu Li
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
| | - Guimin Liu
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
| | - Qing Zhang
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
| | - Haichao Zhao
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
| | - Ruidong Shi
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
| | - Changlin Wang
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
| | - Zihao Li
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
| | - Boyi Zhou
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
| | - Yong Zhang
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing 100072, China
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So S, Yun J, Ko B, Lee D, Kim M, Noh J, Park C, Park J, Rho J. Radiative Cooling for Energy Sustainability: From Fundamentals to Fabrication Methods Toward Commercialization. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2305067. [PMID: 37949679 PMCID: PMC10787071 DOI: 10.1002/advs.202305067] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/18/2023] [Indexed: 11/12/2023]
Abstract
Radiative cooling, a technology that lowers the temperature of terrestrial objects by dissipating heat into outer space, presents a promising ecologically-benign solution for sustainable cooling. Recent years witness substantial progress in radiative cooling technologies, bringing them closer to commercialization. This comprehensive review provides a structured overview of radiative cooling technologies, encompassing essential principles, fabrication techniques, and practical applications, with the goal of guiding researchers toward successful commercialization. The review begins by introducing the fundamentals of radiative cooling and the associated design strategies to achieve it. Then, various fabrication methods utilized for the realization of radiative cooling devices are thoroughly discussed. This discussion includes detailed assessments of scalability, fabrication costs, and performance considerations, encompassing both structural designs and fabrication techniques. Building upon these insights, potential fabrication approaches suitable for practical applications and commercialization are proposed. Further, the recent efforts made toward the practical applications of radiative cooling technology, including its visual appearance, switching capability, and compatibility are examined. By encompassing a broad range of topics, from fundamental principles to fabrication and applications, this review aims to bridge the gap between theoretical research and real-world implementation, fostering the advancement and widespread adoption of radiative cooling technology.
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Affiliation(s)
- Sunae So
- Graduate School of Artificial Intelligence, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
- Department of Electro-Mechanical Systems Engineering, Korea University, Sejong, 30019, Republic of Korea
| | - Jooyeong Yun
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Byoungsu Ko
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Dasol Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
- Department of Biomedical Engineering, Yonsei University, Wonju, 26493, Republic of Korea
| | - Minkyung Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
- School of Mechanical Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Jaebum Noh
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Cherry Park
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Junkyeong Park
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Junsuk Rho
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
- POSCO-POSTECH-RIST Convergence Research Center for Flat Optics and Metaphotonics, Pohang, 37673, Republic of Korea
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Chae D, Lee SY, Lim H, Son S, Ha J, Park J, Park JH, Oh SJ, Lee H. Vivid Colored Cooling Structure Managing Full Solar Spectrum via Near-Infrared Reflection and Photoluminescence. ACS APPLIED MATERIALS & INTERFACES 2023; 15:58274-58285. [PMID: 38051105 DOI: 10.1021/acsami.3c08790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Colored radiative cooling (CRC) offers an attractive alternative for surface and space cooling, while preserving the aesthetics of an object. However, there has been no study on the CRC using phosphors in regard to vivid coloration, sophisticated performance investigation, retention of properties, functionality, and structural flexibility all at once. Thus, to manage the entire solar spectrum, a colored cooling structure comprising a near-infrared (NIR)-reflective bottom layer and a top colored layer with a phosphor-embedded polymer matrix is proposed. The structure is paintable, vividly colored, hydrophobic, and ultraviolet (UV) and water resistant. In the daytime outdoor measurement, the structure with red, orange, and yellow colors exhibited lower temperature than a control group using commercial white paint by 4.7 °C, 7.2 °C, and 7.4 °C, respectively. After precise theoretical and experimental time-tracing temperature validation, the CRC performance enhancement from NIR reflection and photoluminescence effects was thoroughly analyzed, and a temperature reduction of up to 16.1 °C was achieved for the orange-colored structure. Furthermore, experiments of hydrophobicity infusion and exposure to UV and deionized water verified the durability of the colored cooling structure. In addition, flexible-film-type colored cooling structures were demonstrated using different bottom reflective layers, such as a silver thin film and porous aluminum oxide particle-embedded poly(vinylidene fluoride-co-hexafluoropropylene), suggesting the potential applicability of these colored cooling structures for vivid-colored, functional, and durable CRC.
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Affiliation(s)
- Dongwoo Chae
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Sang Yeop Lee
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Hangyu Lim
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Soomin Son
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Jisung Ha
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Jaein Park
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Jun Hyeok Park
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Soong Ju Oh
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Heon Lee
- Department of Materials Science and Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Republic of Korea
- ZERC, 620, New Engineering building, 73-15, Anam-ro, Seongbuk-gu, Seoul Republic of Korea
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Tao S, Han J, Xu Y, Fang Z, Ni Y, Fang L, Lu C, Xu Z. Mechanically Switchable Multifunctional Device for Regulating Passive Radiative Cooling and Solar Heating. ACS APPLIED MATERIALS & INTERFACES 2023; 15:17123-17133. [PMID: 36971527 DOI: 10.1021/acsami.2c21961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Energy consumption during cooling and heating poses a great threat to the development of society. Thermal regulation, as switchable cooling and heating in a single platform, is therefore urgently demanded. Herein, a switchable multifunctional device integrating heating, cooling, and latent energy storage was proposed for temperature regulation and window energy saving for buildings. A radiative cooling (RC) emitter, a phase-change (PC) membrane, and a solar-heating (SH) film were connected layer by layer to form a sandwich structure. The RC emitter exhibited selective infrared emission (emissivity in the atmospheric window: 0.81, emissivity outside the atmospheric window: 0.39) and a high solar reflectance (0.92). Meanwhile, the SH film had a high solar absorptivity (0.90). More importantly, both the RC emitter and the SH film displayed excellent wear resistance and UV resistance. The PC layer can control the temperature at a steady state under dynamic weather conditions, which could be verified by indoor and outdoor measurements. The thermal regulation performance of the multifunctional device was also verified by outdoor measurements. The temperature difference between the RC and SH models of the multifunctional device could reach up to 25 °C. The as-constructed switchable multifunctional device is a promising candidate for alleviating the cooling and heating energy consumption and realizing energy saving for windows.
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Affiliation(s)
- Shuang Tao
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Jingtian Han
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Ying Xu
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Zhenggang Fang
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
| | - Yaru Ni
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, P. R. China
| | - Liang Fang
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, P. R. China
| | - Chunhua Lu
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, P. R. China
| | - Zhongzi Xu
- College of Materials Science and Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 210009, P. R. China
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Jiang T, Fan W, Wang F. Long-Lasting Self-cleaning Daytime Radiative Cooling Paint for Building. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2023.131296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
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Cai X, Gao L, Wang J, Li D. MOF-Integrated Hierarchical Composite Fiber for Efficient Daytime Radiative Cooling and Antibacterial Protective Textiles. ACS APPLIED MATERIALS & INTERFACES 2023; 15:8537-8545. [PMID: 36726324 DOI: 10.1021/acsami.2c21832] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Incorporating passive radiative cooling into textiles is an effective way to improve individual personalized thermophysiological comfort for the human body. Based on radiative cooling textile design, rational functionalization further facilitates practical applications, especially for medical protective products with customized requirements. Herein, we present a hierarchical polyurethane/metal-organic framework (MOF) composite nanofiber membrane with an integrated radiative cooling effect and photocatalytic antibacterial property. Fabricated by a scalable electrospinning method, the hierarchical nanofiber membrane shows high solar reflectance of 97% and improved thermal emissivity of 93% attributed to the abundant chemical bonds in ZIF-8 nanoparticles, rendering a temperature drop of ∼7.2 °C under direct sunlight and ∼5.5 °C at night. In addition, the photocatalytic activity of ZIF-8 ensures a 96% bacterial mortality rate for preventing bacterial infection. In practical application, our composite fabric can prevent superheating by 4.4 °C compared with the traditional protective suit under direct sunlight. Along with its anti-infection ability, the composite fabric is desirable for medical protective textiles. The innovative integration of passive radiative cooling design and functional MOFs breaks through the traditional cooling mode and provides huge substantial advantages for smart textiles and personal cooling applications.
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Affiliation(s)
- Xuan Cai
- College of Chemistry and Materials Science, Jinan University, Guangzhou, Guangdong 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou, Guangdong 510632, P. R. China
| | - Liang Gao
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006, P. R. China
| | - Jizhuang Wang
- College of Chemistry and Materials Science, Jinan University, Guangzhou, Guangdong 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou, Guangdong 510632, P. R. China
| | - Dan Li
- College of Chemistry and Materials Science, Jinan University, Guangzhou, Guangdong 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou, Guangdong 510632, P. R. China
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12
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Meng X, Chen Z, Qian C, Song Z, Wang L, Li Q, Chen X. Hierarchical Superhydrophobic Poly(vinylidene fluoride- co-hexafluoropropylene) Membrane with a Bead (SiO 2 Nanoparticles)-on-String (Nanofibers) Structure for All-Day Passive Radiative Cooling. ACS APPLIED MATERIALS & INTERFACES 2023; 15:2256-2266. [PMID: 36541618 DOI: 10.1021/acsami.2c19422] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Passive all-day radiative cooling has been proposed as a promising pathway to cool objects by reflecting sunlight and dissipating heat to the cold outer space through atmospheric windows without any energy consumption. However, most of the existing radiative coolers are susceptible to contamination, which may decrease the optical property and gradually degrade the outdoor radiative cooling performance. Herein, we prepared a hierarchical superhydrophobic fluorinated-SiO2/PVDF-HFP nanofiber membrane by a facile and scalable technology of electrospinning and electrostatic spraying. Due to the synergistic effects of the efficient scattering of nanofibers/micropores and the phonon polarization resonance of SiO2 nanoparticles, the membrane achieves up to 97.8% average solar reflectance and 96.6% average atmospheric window emittance. The membrane displays sub-ambient temperature drop values of 11.5 and 4.1 °C in daytime and nighttime outdoor conditions, respectively, exhibiting remarkable radiative cooling performance. Importantly, the unique bead (SiO2 nanoparticles)-on-string (nanofibers) structure forms hierarchical roughness that endows the surface with a superior self-cleaning property. In addition, the obtained membrane exhibits remarkable flexibility and mechanical stability, which are of significant importance in cooling vehicles, buildings, and large-scale equipment.
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Affiliation(s)
- Xin Meng
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Zhaochuan Chen
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Chenlu Qian
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Zitao Song
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Lu Wang
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Qiang Li
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Xuemei Chen
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
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13
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Arrés Chillón J, Paulillo B, Mazumder P, Pruneri V. Transparent Glass Surfaces with Silica Nanopillars for Radiative Cooling. ACS APPLIED NANO MATERIALS 2022; 5:17606-17612. [PMID: 36583120 PMCID: PMC9791618 DOI: 10.1021/acsanm.2c03272] [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: 07/26/2022] [Accepted: 10/20/2022] [Indexed: 06/17/2023]
Abstract
The increasing global use of cooling systems and the need of reducing greenhouse effect are pushing the emergence of more efficient cooling methods. In particular, passive radiative cooling technology extracts heat from objects by tailoring their optical emissivity using surface micro- and nanostructuring. Being capable of increasing thermal emissivity is especially relevant for widespread glass structures and devices, e.g., displays, car and building windows, and solar cells. In this paper, we propose a scalable lithography-free nanostructuring method to increase the infrared (IR) emissivity of glass by reducing the high reflection associated with the SiO2 Reststrahlen band around 9 μm wavelength. Furthermore, we show that with an additional thin polymer coating the scattering (haze) in the visible due to the deep nanostructures can be dramatically reduced while maintaining the large IR emissivity. We experimentally prove that our nanostructured surface can extract more heat via radiation emission than the bare glass substrate, while keeping full transparency.
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Affiliation(s)
- Javier Arrés Chillón
- ICFO-Institut
de Ciencies Fotoniques, The Barcelona Institute
of Science and Technology, 08860 Castelldefels, Barcelona, Spain
| | - Bruno Paulillo
- ICFO-Institut
de Ciencies Fotoniques, The Barcelona Institute
of Science and Technology, 08860 Castelldefels, Barcelona, Spain
| | - Prantik Mazumder
- Corning
Research and Development Corporation, Sullivan Park, Corning, New York 14831, United States
| | - Valerio Pruneri
- ICFO-Institut
de Ciencies Fotoniques, The Barcelona Institute
of Science and Technology, 08860 Castelldefels, Barcelona, Spain
- ICREA-Institució
Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys, 23, 08010 Barcelona, Spain
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14
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Wang HD, Xue CH, Ji ZY, Huang MC, Jiang ZH, Liu BY, Deng FQ, An QF, Guo XJ. Superhydrophobic Porous Coating of Polymer Composite for Scalable and Durable Daytime Radiative Cooling. ACS APPLIED MATERIALS & INTERFACES 2022; 14:51307-51317. [PMID: 36320188 DOI: 10.1021/acsami.2c14789] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Passive daytime radiative cooling (PDRC) technology provides an eco-friendly cooling strategy by reflecting sunlight reaching the surface and radiating heat underneath to the outer space through the atmospheric transparency window. However, PDRC materials face challenges in cooling performance degradation caused by outdoor contamination and requirements of easy fabrication approaches for scale-up and high cooling efficiency. Herein, a polymer composite coating of polystyrene, polydimethylsiloxane and poly(ethyl cyanoacrylate) (PS/PDMS/PECA) with superhydrophobicity and radiative cooling performance was fabricated and demonstrated to have sustained radiative cooling capability, utilizing the superhydrophobic self-cleaning property to maintain the optical properties of the coating surface. The prepared coating is hierarchically porous which exhibits an average solar reflectance of 96% with an average emissivity of 95% and superhydrophobicity with a contact angle of 160°. The coating realized a subambient radiative cooling of 12.9 °C in sealed air and 7.5 °C in open air. The self-cleaning property of the PS/PDMS/PECA coating helped sustain the cooling capacity for long-term outdoor applications. Moreover, the coating exhibited chemical resistance, UV resistance, and mechanical durability, which has promising applications in wider fields.
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Affiliation(s)
- Hui-Di Wang
- College of Materials Science and Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
| | - Chao-Hua Xue
- College of Materials Science and Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
| | - Zhan-You Ji
- College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
| | - Meng-Chen Huang
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
| | - Zi-Hao Jiang
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
| | - Bing-Ying Liu
- College of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
| | - Fu-Quan Deng
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
| | - Qiu-Feng An
- College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
| | - Xiao-Jing Guo
- College of Materials Science and Engineering, Shaanxi University of Science and Technology, Xi'an710021, People's Republic of China
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15
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Du T, Niu J, Wang L, Bai J, Wang S, Li S, Fan Y. Daytime Radiative Cooling Coating Based on the Y 2O 3/TiO 2 Microparticle-Embedded PDMS Polymer on Energy-Saving Buildings. ACS APPLIED MATERIALS & INTERFACES 2022; 14:51351-51360. [PMID: 36332077 DOI: 10.1021/acsami.2c15854] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Daytime radiative cooling technology can release heat into outer space without consuming any electricity during the day while reflecting as much solar radiation as possible. This characteristic gives radiative cooling materials considerable application potential in the fields of energy-saving buildings, fabrics, and photovoltaic cells. The radiative cooling coating (RC coating) applied to a building should cover a large area of the building surface, so a RC coating was prepared by spraying. The RC coating consisted of highly near-infrared reflective yttrium oxide (Y2O3), titanium dioxide (TiO2), and polydimethylsiloxane (PDMS). The RC coating could reach a high solar reflectance of 92.2% and a high atmospheric window emissivity of 94.9%. The complementary reflectivity of TiO2 and Y2O3 was the key to obtaining high reflectivity for RC coatings. The results of field tests showed that the cavity where the RC coating is cooled was 7.7 °C lower than the ambient temperature under direct sunlight. Moreover, the average radiative cooling power of the RC coating was 72.5 W/m2 on a hot summer day. In addition, the RC coating has good stability and thus can be used in various conditions, such as on outdoor buildings.
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Affiliation(s)
- Tiantian Du
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin300130, China
| | - Jun Niu
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin300130, China
| | - Leyao Wang
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin300130, China
| | - Jintao Bai
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin300130, China
| | - Shengxing Wang
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin300130, China
| | - Shijie Li
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin300130, China
- Key Lab for New Type of Functional Materials in Hebei Province, Tianjin300130, China
| | - Yongzhe Fan
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin300130, China
- Key Lab for New Type of Functional Materials in Hebei Province, Tianjin300130, China
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16
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Qi G, Tan X, Tu Y, Yang X, Qiao Y, Wang Y, Geng J, Yao S, Chen X. Ordered-Porous-Array Polymethyl Methacrylate Films for Radiative Cooling. ACS APPLIED MATERIALS & INTERFACES 2022; 14:31277-31284. [PMID: 35771521 DOI: 10.1021/acsami.2c06809] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Passive radiative cooling is a spontaneous pattern of reflecting sunlight and radiating heat into the cold outer space through transparent atmosphere windows. In this work, an ordered-porous-array polymethyl methacrylate (OPA-PMMA) film with the properties of excellent radiative cooling is designed and studied. An ultra-high emissivity of 98.4% in the mid-infrared region (3-25 μm) and a good solar reflectance of 85% in the ultraviolet and near-infrared solar spectra (0.2-2.5 μm) were achieved. The surface temperature of the OPA-PMMA film is 16 °C lower than that of the smooth-surface PMMA films and is 8.6 °C lower than that of the commercial white paint in the outdoor test. The structure of the OPA plays an important role in improving solar reflectivity and emissivity. The films are fabricated using a one-step low-cost process that can be applied for large-scale production. It is vital for promoting radiative cooling as a viable energy technology for buildings, fabric, or equipment that need a cooling environment.
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Affiliation(s)
- Guiguang Qi
- Collaborative Innovation Center for New Energy Microgrid, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Electrical Engineering & New Energy, China Three Gorges University, Yichang, Hubei 443002, P. R. China
| | - Xinyu Tan
- Collaborative Innovation Center for New Energy Microgrid, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Electrical Engineering & New Energy, China Three Gorges University, Yichang, Hubei 443002, P. R. China
| | - Yiteng Tu
- Collaborative Innovation Center for New Energy Microgrid, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Electrical Engineering & New Energy, China Three Gorges University, Yichang, Hubei 443002, P. R. China
| | - Xiongbo Yang
- College of Science, China Three Gorges University, Yichang 443002, China
| | - Yulong Qiao
- Collaborative Innovation Center for New Energy Microgrid, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Electrical Engineering & New Energy, China Three Gorges University, Yichang, Hubei 443002, P. R. China
| | - Yunqi Wang
- Collaborative Innovation Center for New Energy Microgrid, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Electrical Engineering & New Energy, China Three Gorges University, Yichang, Hubei 443002, P. R. China
| | - Jialin Geng
- Collaborative Innovation Center for New Energy Microgrid, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Electrical Engineering & New Energy, China Three Gorges University, Yichang, Hubei 443002, P. R. China
| | - Shumin Yao
- Collaborative Innovation Center for New Energy Microgrid, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Electrical Engineering & New Energy, China Three Gorges University, Yichang, Hubei 443002, P. R. China
| | - Xiaobo Chen
- Department of Chemistry, University of Missouri-Kansas City, Kansas City, Missouri 64110, United States
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17
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Shan X, Liu L, Wu Y, Yuan D, Wang J, Zhang C, Wang J. Aerogel-Functionalized Thermoplastic Polyurethane as Waterproof, Breathable Freestanding Films and Coatings for Passive Daytime Radiative Cooling. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2201190. [PMID: 35474617 PMCID: PMC9284144 DOI: 10.1002/advs.202201190] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/07/2022] [Indexed: 06/14/2023]
Abstract
Passive daytime radiative cooling (PDRC) is an emerging sustainable technology that can spontaneously radiate heat to outer space through an atmospheric transparency window to achieve self-cooling. PDRC has attracted considerable attention and shows great potential for personal thermal management (PTM). However, PDRC polymers are limited to polyethylene, polyvinylidene fluoride, and their derivatives. In this study, a series of polymer films based on thermoplastic polyurethane (TPU) and their composite films with silica aerogels (aerogel-functionalized TPU (AFTPU)) are prepared using a simple and scalable non-solvent-phase-separation strategy. The TPU and AFTPU films are freestanding, mechanically strong, show high solar reflection up to 94%, and emit strongly in the atmospheric transparency window, thereby achieving subambient cooling of 10.0 and 7.7 °C on a hot summer day for the TPU and AFTPU film (10 wt%), respectively. The AFTPU films can be used as waterproof and moisture permeable coatings for traditional textiles, such as cotton, polyester, and nylon, and the highest temperature drop of 17.6 °C is achieved with respect to pristine nylon fabric, in which both the cooling performance and waterproof properties are highly desirable for the PTM applications. This study opens up a promising route for designing common polymers for highly efficient PDRC.
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Affiliation(s)
- Xiameng Shan
- School of Nano‐Tech and Nano‐BionicsUniversity of Science and Technology of ChinaHefei230026P. R. China
- Key Laboratory of Multifunctional Nanomaterials and Smart SystemsSuzhou Institute of Nano‐Tech and Nano‐BionicsChinese Academy of SciencesSuzhou215123P. R. China
| | - Ling Liu
- School of Nano‐Tech and Nano‐BionicsUniversity of Science and Technology of ChinaHefei230026P. R. China
- Key Laboratory of Multifunctional Nanomaterials and Smart SystemsSuzhou Institute of Nano‐Tech and Nano‐BionicsChinese Academy of SciencesSuzhou215123P. R. China
| | - Yusi Wu
- Key Laboratory of Multifunctional Nanomaterials and Smart SystemsSuzhou Institute of Nano‐Tech and Nano‐BionicsChinese Academy of SciencesSuzhou215123P. R. China
| | - Dengsen Yuan
- Gusu Laboratory of Materials ScienceSuzhou215123P. R. China
| | - Jing Wang
- School of Nano‐Tech and Nano‐BionicsUniversity of Science and Technology of ChinaHefei230026P. R. China
- Key Laboratory of Multifunctional Nanomaterials and Smart SystemsSuzhou Institute of Nano‐Tech and Nano‐BionicsChinese Academy of SciencesSuzhou215123P. R. China
| | - Chengjiao Zhang
- School of Textile and ClothingNantong UniversityNantong226019P. R. China
| | - Jin Wang
- School of Nano‐Tech and Nano‐BionicsUniversity of Science and Technology of ChinaHefei230026P. R. China
- Key Laboratory of Multifunctional Nanomaterials and Smart SystemsSuzhou Institute of Nano‐Tech and Nano‐BionicsChinese Academy of SciencesSuzhou215123P. R. China
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18
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Cai X, Wang Y, Luo Y, Xu J, Zhao L, Lin Y, Ning Y, Wang J, Gao L, Li D. Rationally Tuning Phase Separation in Polymeric Membranes toward Optimized All-day Passive Radiative Coolers. ACS APPLIED MATERIALS & INTERFACES 2022; 14:27222-27232. [PMID: 35657958 DOI: 10.1021/acsami.2c05943] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The all-day passive radiative cooler has emerged as one of the state-of-the-art energy-saving cooling tool kits but routinely suffers from limited processability, high cost, and complicated fabrication processes, which impede large-scale applications. To address these challenges, this work exploits a polymer-based passive radiative cooler with optimized turbidity, reconfigurability, and recyclability. These cooling membranes are fabricated via selective condensation of octyl side chain-modified polyvinyl alcohol through a non-solvent-induced phase separation method. The rational tuning over spatial organization and distribution of the air-polymer interface renders optimized bright whiteness with solar reflectance at 96%. Meanwhile, the abundant -C-O-C- bonds endow such membranes with infrared thermal emittance over 90%. The optimized membrane realizes a subambient cooling of ∼5.7 °C with an average cooling power of ∼81 W m-2 under a solar intensity of ∼528 W m-2. Furthermore, the supramolecule nature of the developed passive radiative cooling membrane bears enhanced shape malleability and recyclability, substantially enhancing its conformability to the complex geometry and extending its life for an eco-friendly society.
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Affiliation(s)
- Xuan Cai
- College of Chemistry and Materials Science, Jinan University, Guangzhou 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou 510632, P. R. China
| | - Yutao Wang
- College of Chemistry and Materials Science, Jinan University, Guangzhou 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou 510632, P. R. China
| | - Yumin Luo
- College of Chemistry and Materials Science, Jinan University, Guangzhou 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou 510632, P. R. China
| | - Jingyu Xu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Liang Zhao
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Yiyi Lin
- College of Chemistry and Materials Science, Jinan University, Guangzhou 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou 510632, P. R. China
| | - Yin Ning
- College of Chemistry and Materials Science, Jinan University, Guangzhou 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou 510632, P. R. China
| | - Jizhuang Wang
- College of Chemistry and Materials Science, Jinan University, Guangzhou 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou 510632, P. R. China
| | - Liang Gao
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Dan Li
- College of Chemistry and Materials Science, Jinan University, Guangzhou 510632, P. R. China
- Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou 510632, P. R. China
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19
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Ding Z, Pattelli L, Xu H, Sun W, Li X, Pan L, Zhao J, Wang C, Zhang X, Song Y, Qiu J, Li Y, Yang R. Iridescent Daytime Radiative Cooling with No Absorption Peaks in the Visible Range. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2202400. [PMID: 35587771 DOI: 10.1002/smll.202202400] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Indexed: 06/15/2023]
Abstract
Coatings for passive radiative cooling applications must be highly reflected in the solar spectrum, and thus can hardly support any coloration without losing their functionality. In this work, a colorful daytime radiative cooling surface based on structural coloration is reported. A designed radiative cooler with a bioinspired array of truncated SiO2 microcones is manufactured via a self-assembly method and reactive ion etching. Complemented with a silver reflector, the radiative cooler exhibits broadband iridescent coloration due to the scattering induced by the truncated microcone array while maintaining an average reflectance of 95% in the solar spectrum and a high thermal emissivity (ε) of 0.95, owing to the reduced impedance mismatch provided by the patterned surface at infrared wavelengths, reaching an estimated cooling power of ≈143 W m-2 at an ambient temperature of 25 °C and a measured average temperature drop of 7.1 °C under direct sunlight. This strong cooling performance is attributed to its bioinspired surface pattern, which promotes both the aesthetics and cooling capacity of the daytime radiative cooler.
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Affiliation(s)
- Zhenmin Ding
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Lorenzo Pattelli
- Istituto Nazionale di Ricerca Metrologica (INRiM), Turin, 10135, Italy
- European Laboratory for Non-linear Spectroscopy (LENS), Sesto Fiorentino, 50019, Italy
| | - Hongbo Xu
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Wenhai Sun
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Xin Li
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Lei Pan
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Jiupeng Zhao
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Chengyu Wang
- Key Laboratory of Bio-Based Material Science and Technology of Ministry of Education Material Science and Engineering, College Northeast Forestry University, Harbin, 150040, P. R. China
| | - Xiang Zhang
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Ying Song
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Jun Qiu
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Yao Li
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin, 150001, P. R. China
| | - Ronggui Yang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, P. R. China
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20
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Dai B, Li X, Xu T, Zhang X. Radiative Cooling and Solar Heating Janus Films for Personal Thermal Management. ACS APPLIED MATERIALS & INTERFACES 2022; 14:18877-18883. [PMID: 35413199 DOI: 10.1021/acsami.2c01370] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Hot and cold seasonal temperature fluctuations pose a serious public health threat. Radiative thermal management has been shown to be an effective method for personal thermal management. However, the currently available materials cannot maintain human thermal comfort against the hot and cold seasonal temperature fluctuations, such as heating in cold weather or cooling in hot weather. Here, a Janus film that integrates the two opposite requirements of heating and cooling into one functional dual-mode film is fabricated. In cooling mode, the Al backing and embedded silicon dioxide (SiO2) microparticle can achieve a high solar reflectivity (∼0.85) and high IR emissivity (∼0.95) to induce a temperature drop of ∼2 °C. In contrast, the embedded carbon nanotubes (CNTs) can improve solar absorption (∼0.95) and induce a temperature increase of ∼7 °C. Owing to its radiative cooling and solar heating capability and compatibility with large-scale production, this Janus film is promising to bring new insights into the design of the next-generation functional textiles.
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Affiliation(s)
- Bing Dai
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China
| | - Xiangnan Li
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China
| | - Tailin Xu
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China
| | - Xueji Zhang
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China
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21
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Qian HL, Huang WP, Fang Y, Zou LY, Yu WJ, Wang J, Ren KF, Xu ZK, Ji J. Fabrication of "Spongy Skin" on Diversified Materials Based on Surface Swelling Non-Solvent-Induced Phase Separation. ACS APPLIED MATERIALS & INTERFACES 2021; 13:57000-57008. [PMID: 34816710 DOI: 10.1021/acsami.1c18333] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Porous surfaces have attracted tremendous interest for customized incorporation of functional agents on biomedical devices. However, the versatile preparation of porous structures on complicated devices remains challenging. Herein, we proposed a simple and robust method to fabricate "spongy skin" on diversified polymeric substrates based on non-solvent-induced phase separation (NIPS). Through the swelling and the subsequent phase separation process, interconnected porous structures were directly formed onto the polymeric substrates. The thickness and pore size could be regulated in the ranges of 5-200 and 0.3-0.75 μm, respectively. The fast capillary action of the porous structure enabled controllable loading and sustained release of ofloxacin and bovine albumin at a high loading dosage of 79.9 and 24.1 μg/cm2, respectively. We verified that this method was applicable to diversified materials including polymethyl methacrylate, polystyrene, thermoplastic polyurethane, polylactide acid, and poly(lactic-co-glycolic acid) and can be realized onto TCPS cell culture plates. This NIPS-based method is promising to generate porous surfaces on medical devices for incorporating therapeutic agents.
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Affiliation(s)
- Hong-Lin Qian
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Wei-Pin Huang
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Yu Fang
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Ling-Yun Zou
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Wei-Jiang Yu
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jing Wang
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Ke-Feng Ren
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Zhi-Kang Xu
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jian Ji
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
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22
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Banik U, Agrawal A, Meddeb H, Sergeev O, Reininghaus N, Götz-Köhler M, Gehrke K, Stührenberg J, Vehse M, Sznajder M, Agert C. Efficient Thin Polymer Coating as a Selective Thermal Emitter for Passive Daytime Radiative Cooling. ACS APPLIED MATERIALS & INTERFACES 2021; 13:24130-24137. [PMID: 33974398 DOI: 10.1021/acsami.1c04056] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Radiative cooling to subambient temperatures can be efficiently achieved through spectrally selective emission, which until now has only been realized by using complex nanoengineered structures. Here, a simple dip-coated planar polymer emitter derived from polysilazane, which exhibits strong selective emissivity in the atmospheric transparency window of 8-13 μm, is demonstrated. The 5 μm thin silicon oxycarbonitride coating has an emissivity of 0.86 in this spectral range because of alignment of the frequencies of bond vibrations arising from the polymer. Furthermore, atmospheric heat absorption is suppressed due to its low emissivity outside the atmospheric transparency window. The reported structure with the highly transparent polymer and underlying silver mirror reflects 97% of the incoming solar irradiation. A temperature reduction of 6.8 °C below ambient temperature was achieved by the structure under direct sunlight, yielding a cooling power of 93.7 W m-2. The structural simplicity, durability, easy applicability, and high selectivity make polysilazane a unique emitter for efficient prospective passive daytime radiative cooling structures.
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Affiliation(s)
- Udayan Banik
- DLR Institute of Networked Energy Systems, 26129 Oldenburg, Germany
| | - Ashutosh Agrawal
- DLR Institute of Networked Energy Systems, 26129 Oldenburg, Germany
| | - Hosni Meddeb
- DLR Institute of Networked Energy Systems, 26129 Oldenburg, Germany
| | - Oleg Sergeev
- DLR Institute of Networked Energy Systems, 26129 Oldenburg, Germany
| | - Nies Reininghaus
- DLR Institute of Networked Energy Systems, 26129 Oldenburg, Germany
| | | | - Kai Gehrke
- DLR Institute of Networked Energy Systems, 26129 Oldenburg, Germany
| | | | - Martin Vehse
- DLR Institute of Networked Energy Systems, 26129 Oldenburg, Germany
| | - Maciej Sznajder
- DLR Institute of Space Systems, 28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, 28359 Bremen, Germany
| | - Carsten Agert
- DLR Institute of Networked Energy Systems, 26129 Oldenburg, Germany
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23
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Ma H, Wang L, Dou S, Zhao H, Huang M, Xu Z, Zhang X, Xu X, Zhang A, Yue H, Ali G, Zhang C, Zhou W, Li Y, Zhan Y, Huang C. Flexible Daytime Radiative Cooling Enhanced by Enabling Three-Phase Composites with Scattering Interfaces between Silica Microspheres and Hierarchical Porous Coatings. ACS APPLIED MATERIALS & INTERFACES 2021; 13:19282-19290. [PMID: 33866783 DOI: 10.1021/acsami.1c02145] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Daytime radiative cooling has attracted considerable attention recently due to its tremendous potential for passively exploiting the coldness of the universe as clean and renewable energy. Many advanced materials with novel photonic micro/nanostructures have already been developed to enable highly efficient daytime radiative coolers, among which the flexible hierarchical porous coatings (HPCs) are a more distinguished category. However, it is still hard to precisely control the size distribution of the randomized pores within the HPCs, usually resulting in a deficient solar reflection at the near-infrared optical regime under diverse fabrication conditions of the coatings. We report here a three-phase (i.e., air pore-phase, microsphere-phase, and polymer-phase) self-assembled hybrid porous composite coating, which dramatically increases the average solar reflectance and yields remarkable temperature drops of ∼10 and ∼ 30 °C compared to the ambient circumstance and black paint, respectively, according to the rooftop measurements. Mie theory and Monte Carlo simulations reveal the origin of the low reflectivity of as-prepared two-phase porous HPCs, and the optical cooling improvement of the three-phase porous composite coatings is attributed to the newly generated interfaces possessing the high scattering efficiency between the hierarchical pores and silica microspheres hybridized with appropriate mass fractions. As a result, the hybrid porous composite approach enhances the whole performance of the coatings, which provides a promising alternative to the flexible daytime radiative cooler.
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Affiliation(s)
- Hongchen Ma
- School of Optoelectronic Science and Engineering & Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Liang Wang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
| | - Shuliang Dou
- National Key Laboratory of Science and Technology on Advanced Composites, Harbin Institute of Technology, Harbin 150001, China
| | - Haipeng Zhao
- School of Optoelectronic Science and Engineering & Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Min Huang
- School of Optoelectronic Science and Engineering & Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Zewen Xu
- Soochow Institute for Energy and Materials Innovations, College of Energy, Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Xinyuan Zhang
- School of Optoelectronic Science and Engineering & Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Xiudong Xu
- School of Optoelectronic Science and Engineering & Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Aiqin Zhang
- Soochow Institute for Energy and Materials Innovations, College of Energy, Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Huiyu Yue
- Soochow Institute for Energy and Materials Innovations, College of Energy, Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Ghulam Ali
- Soochow Institute for Energy and Materials Innovations, College of Energy, Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
| | - Caihua Zhang
- Soochow Institute for Energy and Materials Innovations, College of Energy, Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
- School of Chemistry and Chemical Engineering, Xi'an University of Science and Technology, Xi'an 710054, China
| | - Wenying Zhou
- School of Chemistry and Chemical Engineering, Xi'an University of Science and Technology, Xi'an 710054, China
| | - Yao Li
- National Key Laboratory of Science and Technology on Advanced Composites, Harbin Institute of Technology, Harbin 150001, China
| | - Yaohui Zhan
- School of Optoelectronic Science and Engineering & Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
- Light Industry Institute of Electrochemical Power Sources, Zhangjiagang 215600, China
| | - Cheng Huang
- Soochow Institute for Energy and Materials Innovations, College of Energy, Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou 215006, China
- Light Industry Institute of Electrochemical Power Sources, Zhangjiagang 215600, China
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