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Harish C. Barshilia - One of the best experts on this subject based on the ideXlab platform.
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extremely high temperature stable nanometric scale multilayer spectrally Selective Absorber coating emissivity measurements at elevated temperatures and a comprehensive study on ageing mechanism
Solar Energy Materials and Solar Cells, 2021Co-Authors: Audrey Soumglaude, Alex Carlingplaza, K Niranjan, Sandip Bysakh, Siju John, Harish C. BarshiliaAbstract:Abstract Spectrally Selective W/WAlSiN/SiON/SiO2 solar Absorber coatings were sputter-deposited on stainless steel and silicon substrates. The optimized as-deposited sample exhibits a high solar absorptance of 0.955 and a low thermal emissivity of 0.10 at 82 °C. The coating exhibits a very low reflectance of 1.2% in the wavelength range of 0.5–1.5 μm in the solar spectrum. The spectral emissivity measurements at various operating temperatures and with varying emergence angles were investigated. Also, the impact of emissivity on the photothermal efficiency at different temperatures of the developed solar Absorber coating was calculated. The calculated optical properties of the as-deposited sample exhibited low thermal emissivity of 0.157 (at 500 °C) and a high heliothermal efficiency of 89.5%. Angular reflectance measured at room temperature illustrates an insignificant change in the hemispherical and near normal emissivities of the samples. In addition to these studies, the ageing tests of the as-deposited samples at various operating temperatures were studied in detail. The thermal ageing tests of the samples in air and vacuum environments indicated excellent thermal stability at elevated temperatures, i.e., in air at 400 °C for 500 h, at 450 °C for 175 h and at 500 °C for 100 h, whereas, in a vacuum it was stable at 700 °C for 200 h. The top anti-reflection layers and the fine nano-multilayers of WAlSiN (W2N and AlSiN) prevent the inward diffusion of oxygen and thereby improve the overall thermal stability of the tandem Absorber.
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temperature and angle dependent emissivity and thermalshock resistance of the w waln walon al 2 o 3 basedspectrally Selective Absorber
ACS Applied Energy Materials, 2019Co-Authors: Atasi Dan, Harish C. Barshilia, Audrey Soumglaude, K Chattopadhyay, Alex Carlingplaza, Bikramjit BasuAbstract:Spectral emissivity is considered as one of the most critical thermophysical properties influencing photothermal conversion efficiency of solar Selective Absorbers. In addition, long-term stability...
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temperature and angle dependent emissivity and thermalshock resistance of the w waln walon al 2 o 3 basedspectrally Selective Absorber
ACS Applied Energy Materials, 2019Co-Authors: Audrey Soumglaude, Harish C. Barshilia, K Chattopadhyay, Alex Carlingplaza, Clifford K Ho, Bikramjit BasuAbstract:Spectral emissivity is considered as one of the most critical thermophysical properties influencing photothermal conversion efficiency of solar Selective Absorbers. In addition, long-term stability at high temperature and thermal shock resistance are the performance-limiting properties of spectrally Selective Absorbers. In this context, this study reports the variation of emissivity with a change in emergence angles and operational temperatures for the newly developed W/WAlN/WAlON/Al2O3 Absorber. An analysis of the experimental results demonstrates that hemispherical emissivity values at elevated temperature are comparable while calculated using both room temperature and high temperature reflectance data. Hence, the applicability of the room temperature measurement method is validated to evaluate high temperature emissivity. The analysis of angular measurements indicates an insignificant difference between hemispherical and near-normal emissivity values for W/WAlN/WAlON/Al2O3. The study suggests that hemi...
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enhancing spectrally Selective response of w waln walon al2o3 based nanostructured multilayer Absorber coating through graded optical constants
Solar Energy Materials and Solar Cells, 2018Co-Authors: Atasi Dan, Harish C. Barshilia, K Chattopadhyay, Arup Biswas, P Sarkar, Sanjay Kashyap, Bikramjit BasuAbstract:In the field of concentrating solar power (CSP) technologies, multilayer Absorber coatings are widely being investigated. The spectral properties of Selective coatings can be tailored by carefully adjusting the composition and thickness of each layer. Based on the extensive analysis using the transmission electron microscopy (TEM), phase modulated spectroscopic ellipsometry along with computational study, we demonstrate how we can engineer the optical constants (refractive index and extinction coefficient) of individual layer to successfully achieve the spectrally Selective properties in W/WAlN/WAlON/Al2O3 - based multilayer Absorber coating. This coating exhibits a high absorptance of 0.958 and a low emittance of 0.08. The spectroscopic ellipsometry study confirmed the variation in metallic and optical properties of single layer of WAlN, WAlON and Al2O3 films, deposited on stainless steel substrates. This study also revealed the presence of intermediate layers of 26% WAlN - 74% WAlON at WAlN/WAlON interface and 60% WAlON - 40% Al2O3 at WAlON/Al2O3 interface. The Tauc - Lorentz dispersion model could effectively interpret the ellipsometry data of single layers of WAlN and Al2O3, while Cauchy absorbent model was useful for WAlON coating. Bruggeman effective medium approximation was used to describe the optical functions of intermediate layers. Investigation on optical constants reveals that the refractive index and extinction coefficient of each layer decrease from substrate to surface. The computational predictions of the reflectance properties corroborate well with the experimental results. In summary, the careful engineering of the optical properties in W/WAlN/WAlON/Al2O3 enables it to be an exceptional spectrally Selective Absorber coating.
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solar energy absorption mediated by surface plasma polaritons in spectrally Selective dielectric metal dielectric coatings a critical review
Renewable & Sustainable Energy Reviews, 2017Co-Authors: Harish C. Barshilia, K Chattopadhyay, Bikramjit BasuAbstract:The effective use of solar energy has become significantly important due to unnatural weather changes and fossil fuel exhaustion. Concentrating Solar Power (CSP) technology is a promising approach to harvest solar energy in the form of heat using solar Selective Absorber coating. These coatings are expected to absorb maximum incoming solar radiation (α ≥ 0.95) and prevent loss of the absorbed energy as infrared radiation (e ≤ 0.05). Efficiency of the Absorber coating can be evaluated by a metric called “Solar selectivity (α/e)”. In recent years, a number of attempts have been made to achieve remarkable Selective property and high temperature stability of the Absorber coating using the concept of Surface Plasma Polaritons (SPPs). The SPPs have the capability to capture solar energy by confining electromagnetic field at the metal-dielectric interface. Solar absorption, can be maximized by tailoring the optical constants of the metal and dielectric. In this review, we have described different types of solar Absorber coatings with particular emphasis on dielectric-metal-dielectric (DMD) -based Absorber coatings. We have presented a brief theoretical overview to comprehend physics of DMD coatings. This review additionally highlights some of the case studies based on the DMD -based Absorber coatings with the high temperature stability and their importance in the context of CSP technologies.
Bikramjit Basu - One of the best experts on this subject based on the ideXlab platform.
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temperature and angle dependent emissivity and thermalshock resistance of the w waln walon al 2 o 3 basedspectrally Selective Absorber
ACS Applied Energy Materials, 2019Co-Authors: Audrey Soumglaude, Harish C. Barshilia, K Chattopadhyay, Alex Carlingplaza, Clifford K Ho, Bikramjit BasuAbstract:Spectral emissivity is considered as one of the most critical thermophysical properties influencing photothermal conversion efficiency of solar Selective Absorbers. In addition, long-term stability at high temperature and thermal shock resistance are the performance-limiting properties of spectrally Selective Absorbers. In this context, this study reports the variation of emissivity with a change in emergence angles and operational temperatures for the newly developed W/WAlN/WAlON/Al2O3 Absorber. An analysis of the experimental results demonstrates that hemispherical emissivity values at elevated temperature are comparable while calculated using both room temperature and high temperature reflectance data. Hence, the applicability of the room temperature measurement method is validated to evaluate high temperature emissivity. The analysis of angular measurements indicates an insignificant difference between hemispherical and near-normal emissivity values for W/WAlN/WAlON/Al2O3. The study suggests that hemi...
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temperature and angle dependent emissivity and thermalshock resistance of the w waln walon al 2 o 3 basedspectrally Selective Absorber
ACS Applied Energy Materials, 2019Co-Authors: Atasi Dan, Harish C. Barshilia, Audrey Soumglaude, K Chattopadhyay, Alex Carlingplaza, Bikramjit BasuAbstract:Spectral emissivity is considered as one of the most critical thermophysical properties influencing photothermal conversion efficiency of solar Selective Absorbers. In addition, long-term stability...
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enhancing spectrally Selective response of w waln walon al2o3 based nanostructured multilayer Absorber coating through graded optical constants
Solar Energy Materials and Solar Cells, 2018Co-Authors: Atasi Dan, Harish C. Barshilia, K Chattopadhyay, Arup Biswas, P Sarkar, Sanjay Kashyap, Bikramjit BasuAbstract:In the field of concentrating solar power (CSP) technologies, multilayer Absorber coatings are widely being investigated. The spectral properties of Selective coatings can be tailored by carefully adjusting the composition and thickness of each layer. Based on the extensive analysis using the transmission electron microscopy (TEM), phase modulated spectroscopic ellipsometry along with computational study, we demonstrate how we can engineer the optical constants (refractive index and extinction coefficient) of individual layer to successfully achieve the spectrally Selective properties in W/WAlN/WAlON/Al2O3 - based multilayer Absorber coating. This coating exhibits a high absorptance of 0.958 and a low emittance of 0.08. The spectroscopic ellipsometry study confirmed the variation in metallic and optical properties of single layer of WAlN, WAlON and Al2O3 films, deposited on stainless steel substrates. This study also revealed the presence of intermediate layers of 26% WAlN - 74% WAlON at WAlN/WAlON interface and 60% WAlON - 40% Al2O3 at WAlON/Al2O3 interface. The Tauc - Lorentz dispersion model could effectively interpret the ellipsometry data of single layers of WAlN and Al2O3, while Cauchy absorbent model was useful for WAlON coating. Bruggeman effective medium approximation was used to describe the optical functions of intermediate layers. Investigation on optical constants reveals that the refractive index and extinction coefficient of each layer decrease from substrate to surface. The computational predictions of the reflectance properties corroborate well with the experimental results. In summary, the careful engineering of the optical properties in W/WAlN/WAlON/Al2O3 enables it to be an exceptional spectrally Selective Absorber coating.
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solar energy absorption mediated by surface plasma polaritons in spectrally Selective dielectric metal dielectric coatings a critical review
Renewable & Sustainable Energy Reviews, 2017Co-Authors: Harish C. Barshilia, K Chattopadhyay, Bikramjit BasuAbstract:The effective use of solar energy has become significantly important due to unnatural weather changes and fossil fuel exhaustion. Concentrating Solar Power (CSP) technology is a promising approach to harvest solar energy in the form of heat using solar Selective Absorber coating. These coatings are expected to absorb maximum incoming solar radiation (α ≥ 0.95) and prevent loss of the absorbed energy as infrared radiation (e ≤ 0.05). Efficiency of the Absorber coating can be evaluated by a metric called “Solar selectivity (α/e)”. In recent years, a number of attempts have been made to achieve remarkable Selective property and high temperature stability of the Absorber coating using the concept of Surface Plasma Polaritons (SPPs). The SPPs have the capability to capture solar energy by confining electromagnetic field at the metal-dielectric interface. Solar absorption, can be maximized by tailoring the optical constants of the metal and dielectric. In this review, we have described different types of solar Absorber coatings with particular emphasis on dielectric-metal-dielectric (DMD) -based Absorber coatings. We have presented a brief theoretical overview to comprehend physics of DMD coatings. This review additionally highlights some of the case studies based on the DMD -based Absorber coatings with the high temperature stability and their importance in the context of CSP technologies.
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spectrally Selective Absorber coating of waln walon al2o3 for solar thermal applications
Solar Energy Materials and Solar Cells, 2016Co-Authors: Atasi Dan, Harish C. Barshilia, K Chattopadhyay, J Jyothi, Bikramjit BasuAbstract:A novel WAlN/WAlON/Al2O3 coating was successfully deposited on stainless steel (SS) substrate using reactive DC and RF magnetron sputtering. Excellent spectrally Selective property with a high absorptance of 0.958 in the solar spectrum region and low emittance of 0.08 in the infrared region were achieved by tailoring the target power, deposition time and the reactive flow rates of N-2 and O-2. In the present solar Selective coating, W layer acts as a back reflector and diffusion barrier, WAlN as the main Absorber layer, WAlON as the semi-Absorber layer, whereas the topmost Al2O3 layer works as an anti-reflecting layer. In reference to the thermal stability, the Absorber deposited on SS substrates exhibited high solar selectivity (alpha/epsilon) of 0.920/0.11, when heat treated in air up to 500 degrees C for 2 hrs. Taken together, the present study demonstrated that the WAlN/WAlON/Al2O3-based Selective absorbing coating with excellent thermal stability could be a promising material for photo-thermal conversion at temperatures of up to 500 degrees C. (C) 2016 Elsevier B.V. All rights reserved.
N. Selvakumar - One of the best experts on this subject based on the ideXlab platform.
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carbon nanotube based tandem Absorber with tunable spectral selectivity transition from near perfect blackbody Absorber to solar Selective Absorber
Advanced Materials, 2014Co-Authors: S. B. Krupanidhi, N. Selvakumar, Harish C. BarshiliaAbstract:Carbon nanotubes (CNTs) have good optical properties (i.e., absorptance (α) and emittance (e) close to 1), high aspect ratios (>150), high surface area (470 m2/g) and high thermal conductivity (>3000 W/m.K), which enable rapid heat transfer from the CNTs to the substrates.[1-4] Various researchers have reported the usage of CNT forests for solar thermal energy conversion applications.[5-7] But the major disadvantage of using CNT forest for solar thermal applications is that they have poor spectral selectivity (i.e., α/e = 1). CNTs with tunable spectral selectivity (i.e., high α in the visible region and low e in the infrared region) and the effect of CNT lengths on their optical properties are emerging areas of research and have not been discussed in the literature. In the present work, we have grown CNT- based tandem Absorber on stainless steel (SS 304) substrates and demonstrated the transition from near-perfect blackbody Absorber to solar Selective Absorber by varying the thicknesses of CNTs and by suitably designing the bottom tandem Absorber. The CNT based tandem Absorbers exhibit higher thermal stability in vacuum as compared to the existing solar thermal coatings.
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carbon nanotube based tandem Absorber with tunable spectral selectivity transition from near perfect blackbody Absorber to solar Selective Absorber
Advanced Materials, 2014Co-Authors: S. B. Krupanidhi, N. Selvakumar, Harish C. BarshiliaAbstract:CVD grown CNT thin film with a thickness greater than 10 μm behaves like a near-perfect blackbody Absorber (i.e., α/e = 0.99/0.99). Whereas, for a thickness ≤ 0.4 µm, the CNT based tandem Absorber acts as a spectrally Selective coating (i.e., α/e = 0.95/0.20). These Selective coatings exhibit thermal stability up to 650 °C in vacuum, which can be used for solar thermal power generation.
Jifeng Liu - One of the best experts on this subject based on the ideXlab platform.
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design and optimization of nanoparticle pigmented solar Selective Absorber coatings for high temperature concentrating solar thermal systems
Journal of Applied Physics, 2018Co-Authors: Xiaoxin Wang, Eldred Lee, Katerina Kekalo, Jifeng LiuAbstract:We present a systematic approach for the design and optimization of nanoparticle-pigmented solar Selective Absorbers for operation at 750 °C. Using the scattering and absorption cross-sections calculated by Lorenz-Mie scattering theory as input, we employ a four-flux radiative transfer method to investigate the solar selectivity mechanism and optimize the optical-to-thermal conversion efficiency (ηtherm) as a function of the metallic nanoparticle material, the nanoparticle diameter, the volume fraction, and the coating thickness. Among the nanoparticle material candidates in this study, C54-TiSi2 is the best option with an optimized ηtherm = 87.0% for a solar concentration ratio of C = 100 and ηtherm = 94.4% for C = 1000 at 750 °C. NiSi is also a promising candidate comparable to TiSi2 in thermal efficiency. Experimentally, an un-optimized 200 nm-diameter TiSi2 nanoparticle-silicone solar Selective coating has already achieved ηtherm = 89.8% for C = 1000 at 750 °C. This performance is consistent with the ...
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design and optimization of nanoparticle pigmented solar Selective Absorber coatings for high temperature concentrating solar thermal systems
Journal of Applied Physics, 2018Co-Authors: Xiaoxin Wang, Eldred Lee, Katerina Kekalo, Jifeng LiuAbstract:We present a systematic approach for the design and optimization of nanoparticle-pigmented solar Selective Absorbers for operation at 750 °C. Using the scattering and absorption cross-sections calculated by Lorenz-Mie scattering theory as input, we employ a four-flux radiative transfer method to investigate the solar selectivity mechanism and optimize the optical-to-thermal conversion efficiency (ηtherm) as a function of the metallic nanoparticle material, the nanoparticle diameter, the volume fraction, and the coating thickness. Among the nanoparticle material candidates in this study, C54-TiSi2 is the best option with an optimized ηtherm = 87.0% for a solar concentration ratio of C = 100 and ηtherm = 94.4% for C = 1000 at 750 °C. NiSi is also a promising candidate comparable to TiSi2 in thermal efficiency. Experimentally, an un-optimized 200 nm-diameter TiSi2 nanoparticle-silicone solar Selective coating has already achieved ηtherm = 89.8% for C = 1000 at 750 °C. This performance is consistent with the theoretical model and close to the thermal efficiency of the commercial Pyromark 2500 coatings (90.1%). We also demonstrate that Ni/NiSi core-shell structures embedded in the SiO1.5 matrix is thermally stable at 750 °C for 1000 h in air. These results indicate that silicide cermet coatings are promising to achieve high optical performance and high temperature thermal stability simultaneously.
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interfacial engineering of solution processed ni nanochain siox x 2 cermets towards thermodynamically stable anti oxidation solar Selective Absorbers
Journal of Applied Physics, 2016Co-Authors: Xiaoxin Wang, Qinglin Zhang, Jifeng LiuAbstract:Cermet solar thermal Selective Absorber coatings are an important component of high-efficiency concentrated solar power (CSP) receivers. The oxidation of the metal nanoparticles in cermet solar Absorbers is a great challenge for vacuum-free operation. Recently, we have demonstrated that oxidation is kinetically retarded in solution processed, high-optical-performance Ni nanochain-SiOx cermet system compared to conventional Ni-Al2O3 system when annealed in air at 450–600 °C for several hours. However, for long-term, high-temperature applications in CSP systems, thermodynamically stable antioxidation behavior is highly desirable, which requires new mechanisms beyond kinetically reducing the oxidation rate. Towards this goal, in this paper, we demonstrate that pre-operation annealing of Ni nanochain-SiOx cermets at 900 °C in N2 forms the thermodynamically stable orthorhombic phase of NiSi at the Ni/SiOx interfaces, leading to self-terminated oxidation at 550 °C in air due to this interfacial engineering. In ...
K Chattopadhyay - One of the best experts on this subject based on the ideXlab platform.
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temperature and angle dependent emissivity and thermalshock resistance of the w waln walon al 2 o 3 basedspectrally Selective Absorber
ACS Applied Energy Materials, 2019Co-Authors: Audrey Soumglaude, Harish C. Barshilia, K Chattopadhyay, Alex Carlingplaza, Clifford K Ho, Bikramjit BasuAbstract:Spectral emissivity is considered as one of the most critical thermophysical properties influencing photothermal conversion efficiency of solar Selective Absorbers. In addition, long-term stability at high temperature and thermal shock resistance are the performance-limiting properties of spectrally Selective Absorbers. In this context, this study reports the variation of emissivity with a change in emergence angles and operational temperatures for the newly developed W/WAlN/WAlON/Al2O3 Absorber. An analysis of the experimental results demonstrates that hemispherical emissivity values at elevated temperature are comparable while calculated using both room temperature and high temperature reflectance data. Hence, the applicability of the room temperature measurement method is validated to evaluate high temperature emissivity. The analysis of angular measurements indicates an insignificant difference between hemispherical and near-normal emissivity values for W/WAlN/WAlON/Al2O3. The study suggests that hemi...
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temperature and angle dependent emissivity and thermalshock resistance of the w waln walon al 2 o 3 basedspectrally Selective Absorber
ACS Applied Energy Materials, 2019Co-Authors: Atasi Dan, Harish C. Barshilia, Audrey Soumglaude, K Chattopadhyay, Alex Carlingplaza, Bikramjit BasuAbstract:Spectral emissivity is considered as one of the most critical thermophysical properties influencing photothermal conversion efficiency of solar Selective Absorbers. In addition, long-term stability...
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enhancing spectrally Selective response of w waln walon al2o3 based nanostructured multilayer Absorber coating through graded optical constants
Solar Energy Materials and Solar Cells, 2018Co-Authors: Atasi Dan, Harish C. Barshilia, K Chattopadhyay, Arup Biswas, P Sarkar, Sanjay Kashyap, Bikramjit BasuAbstract:In the field of concentrating solar power (CSP) technologies, multilayer Absorber coatings are widely being investigated. The spectral properties of Selective coatings can be tailored by carefully adjusting the composition and thickness of each layer. Based on the extensive analysis using the transmission electron microscopy (TEM), phase modulated spectroscopic ellipsometry along with computational study, we demonstrate how we can engineer the optical constants (refractive index and extinction coefficient) of individual layer to successfully achieve the spectrally Selective properties in W/WAlN/WAlON/Al2O3 - based multilayer Absorber coating. This coating exhibits a high absorptance of 0.958 and a low emittance of 0.08. The spectroscopic ellipsometry study confirmed the variation in metallic and optical properties of single layer of WAlN, WAlON and Al2O3 films, deposited on stainless steel substrates. This study also revealed the presence of intermediate layers of 26% WAlN - 74% WAlON at WAlN/WAlON interface and 60% WAlON - 40% Al2O3 at WAlON/Al2O3 interface. The Tauc - Lorentz dispersion model could effectively interpret the ellipsometry data of single layers of WAlN and Al2O3, while Cauchy absorbent model was useful for WAlON coating. Bruggeman effective medium approximation was used to describe the optical functions of intermediate layers. Investigation on optical constants reveals that the refractive index and extinction coefficient of each layer decrease from substrate to surface. The computational predictions of the reflectance properties corroborate well with the experimental results. In summary, the careful engineering of the optical properties in W/WAlN/WAlON/Al2O3 enables it to be an exceptional spectrally Selective Absorber coating.
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solar energy absorption mediated by surface plasma polaritons in spectrally Selective dielectric metal dielectric coatings a critical review
Renewable & Sustainable Energy Reviews, 2017Co-Authors: Harish C. Barshilia, K Chattopadhyay, Bikramjit BasuAbstract:The effective use of solar energy has become significantly important due to unnatural weather changes and fossil fuel exhaustion. Concentrating Solar Power (CSP) technology is a promising approach to harvest solar energy in the form of heat using solar Selective Absorber coating. These coatings are expected to absorb maximum incoming solar radiation (α ≥ 0.95) and prevent loss of the absorbed energy as infrared radiation (e ≤ 0.05). Efficiency of the Absorber coating can be evaluated by a metric called “Solar selectivity (α/e)”. In recent years, a number of attempts have been made to achieve remarkable Selective property and high temperature stability of the Absorber coating using the concept of Surface Plasma Polaritons (SPPs). The SPPs have the capability to capture solar energy by confining electromagnetic field at the metal-dielectric interface. Solar absorption, can be maximized by tailoring the optical constants of the metal and dielectric. In this review, we have described different types of solar Absorber coatings with particular emphasis on dielectric-metal-dielectric (DMD) -based Absorber coatings. We have presented a brief theoretical overview to comprehend physics of DMD coatings. This review additionally highlights some of the case studies based on the DMD -based Absorber coatings with the high temperature stability and their importance in the context of CSP technologies.
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spectrally Selective Absorber coating of waln walon al2o3 for solar thermal applications
Solar Energy Materials and Solar Cells, 2016Co-Authors: Atasi Dan, Harish C. Barshilia, K Chattopadhyay, J Jyothi, Bikramjit BasuAbstract:A novel WAlN/WAlON/Al2O3 coating was successfully deposited on stainless steel (SS) substrate using reactive DC and RF magnetron sputtering. Excellent spectrally Selective property with a high absorptance of 0.958 in the solar spectrum region and low emittance of 0.08 in the infrared region were achieved by tailoring the target power, deposition time and the reactive flow rates of N-2 and O-2. In the present solar Selective coating, W layer acts as a back reflector and diffusion barrier, WAlN as the main Absorber layer, WAlON as the semi-Absorber layer, whereas the topmost Al2O3 layer works as an anti-reflecting layer. In reference to the thermal stability, the Absorber deposited on SS substrates exhibited high solar selectivity (alpha/epsilon) of 0.920/0.11, when heat treated in air up to 500 degrees C for 2 hrs. Taken together, the present study demonstrated that the WAlN/WAlON/Al2O3-based Selective absorbing coating with excellent thermal stability could be a promising material for photo-thermal conversion at temperatures of up to 500 degrees C. (C) 2016 Elsevier B.V. All rights reserved.