Coatings

11 pages, 5086 KiB

Open AccessArticle

Comprehensive Study of Au Nano-Mesh as a Catalyst in the Fabrication of Silicon Nanowires Arrays by Metal-Assisted Chemical Etching

by Shanshan Wang, Huan Liu and Jun Han

Coatings 2019, 9(2), 149; https://doi.org/10.3390/coatings9020149 - 25 Feb 2019

Cited by 12 | Viewed by 4062

Abstract

Silicon nanowires (SiNWs) arrays have become one of low-dimensional structural nanomaterials for the preparation of high-performance optoelectronic devices with the advantages of highly efficient light trapping effect, carrier multiplication, and adjustable optical bandgap. The controlled growth of SiNWs determines their electrical and optical [...] Read more.

Silicon nanowires (SiNWs) arrays have become one of low-dimensional structural nanomaterials for the preparation of high-performance optoelectronic devices with the advantages of highly efficient light trapping effect, carrier multiplication, and adjustable optical bandgap. The controlled growth of SiNWs determines their electrical and optical properties. The morphology of silicon nanowires fabricated by conventional metal-assisted chemical etching (MACE) involving the Ag-based etching process cannot be precisely controlled. Ultra-thin anodic aluminum oxide (AAO) is one of the new-pattern nanostructure assembly systems for the synthesis of nanomaterials. The synthesized nanostructure arrays can be tuned to exhibit different optical and electrical properties in a certain wavelength range by adjusting the AAO membrane parameters. In this paper, we demonstrate an ultra-thin Au nano-meshes array from a single hexagonal AAO membrane as a replication master instead of conventional Ag particles as etching catalyst. The extended ordered silicon nanowires arrays are fabricated by the selective chemical dissolution of nanoscale noble metal meshes that exhibit excellent anti-reflection performance in broadband wavelengths and a wide incidence angle. Full article

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12 pages, 4786 KiB

Open AccessArticle

Synthesis and Properties of Electrodeposited Ni–Co/WS₂ Nanocomposite Coatings

by Yang He, Shuncai Wang, Wanting Sun, Philippa A.S. Reed and Frank C. Walsh

Coatings 2019, 9(2), 148; https://doi.org/10.3390/coatings9020148 - 25 Feb 2019

Cited by 10 | Viewed by 4387

Abstract

Ni–Co coatings have gained widespread attention due to their potential in replacing hard chromium deposits (which have traditionally utilized toxic and corrosive chromic acid baths). A major challenge is to lower the high coefficient of friction of coated surfaces against steel, under dry [...] Read more.

Ni–Co coatings have gained widespread attention due to their potential in replacing hard chromium deposits (which have traditionally utilized toxic and corrosive chromic acid baths). A major challenge is to lower the high coefficient of friction of coated surfaces against steel, under dry sliding conditions. In this research, low friction Ni–Co/WS₂ nanocomposite coatings have been prepared by a convenient, one-pot electrodeposition from aqueous Ni–Co plating baths containing WS₂ particles. The embedment of the WS₂ lubricants is found to reduce the friction coefficient of coating significantly, and an ultra-low friction coefficient of 0.16 is obtained for the coating having a WS₂ content of 7.1 wt.%. Morphology and composition characterization of wear tracks reveal that the formation of a WS₂-rich lubricating tribofilm on the contact surfaces is beneficial to a low friction coefficient and good oxidation resistance. The wettability of electrodeposited coatings was also investigated. Compared to pure Ni-Co coating, the Ni–Co/7.1 wt.% WS₂ coating has an excellent hydrophobicity with a high water contact angle (WCA) of 157°, due to a rough surface with dual scale protrusions and the low surface energy of WS₂. Full article

(This article belongs to the Special Issue Superhydrophobic Coatings for Corrosion and Tribology)

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13 pages, 4967 KiB

Open AccessArticle

Manufacturing of Double Layer Optical Fiber Coating Using Phan-Thien-Tanner Fluid as Coating Material

by Zeeshan Khan, Haroon Ur Rasheed, S.O. Alharbi, Ilyas Khan, Tariq Abbas and Dennis Ling Chuan Chin

Coatings 2019, 9(2), 147; https://doi.org/10.3390/coatings9020147 - 24 Feb 2019

Cited by 18 | Viewed by 4010

Abstract

Modern optical fiber required a double-layer resin coating on the glass fiber to provide protection from signal attenuation and mechanical damage. The most important plastics resin used in coating of fiber optics are plasticized polyvinyle (PVC), low/high density polyethylene (LDPE/HDPE), nylon, and polysulfone. [...] Read more.

Modern optical fiber required a double-layer resin coating on the glass fiber to provide protection from signal attenuation and mechanical damage. The most important plastics resin used in coating of fiber optics are plasticized polyvinyle (PVC), low/high density polyethylene (LDPE/HDPE), nylon, and polysulfone. Polymer flow during optical fiber coating in a pressure type coating die has been simulated under non-isothermal conditions. The flow dependent on the wire or fiber velocity, geometry of the die, and the viscosity of the polymer. The wet-on-wet coating process is an efficient process for two-layer coating on the fiber optics. In the present study, the constitutive equation of polymer flow satisfies viscoelastic Phan-Thien-Tanner (PTT) fluid, is used to characterize rheology of the polymer melt. Based on the assumption of the fully developed incompressible and laminar flow, the viscoelastic fluid model of two-immiscible resins-layers modeled for simplified-geometry of capillary-annulus where the glass fiber drawing inside the die at high speed. The equation describing the flow of the polymer melt inside the die was solved, analytically and numerically, by the Runge-Kutta method. The effect of physical characteristics in the problem has been discussed in detail through graphs by assigning numerical values for several parameters of interest. It is observed that velocity increases with increasing values of

ε D_{1}^{2}, ε D_{2}^{2}

,

X_{1}

, and

X_{2}

. The volume flow rate increases with an increasing Deborah number. The thickness of coated fiber optic increases with increasing

ε D_{1}^{2}

,

ε D_{2}^{2}

, and

δ

. Increase in Brinkman number and Deborah number enhances the rate of heat transfer. It is our first attempt to model PTT fluid as a coating material for double-layer optical fiber coating using the wet-on-wet coating process. At the end, the present study is also compared with the published work as a particular case, and good agreement is found. Full article

(This article belongs to the Special Issue Recent Trends in Coatings and Thin Film–Modeling and Application)

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17 pages, 1925 KiB

Open AccessArticle

Analysis of Linear Non-Destructive Testing and Evaluation Methods for Thin-Walled Structure Inspection Using Ultrasonic Array

by Yang Li, Zhenggan Zhou and Jun Wang

Coatings 2019, 9(2), 146; https://doi.org/10.3390/coatings9020146 - 22 Feb 2019

Cited by 1 | Viewed by 3547

Abstract

The ultrasonic array used for thin-walled structure non-destructive inspection usually has a high central frequency so that the thickness-to-acoustic wavelength ratio is greater than 10. When the ratio is much smaller than 10, the reliability of the conventional ultrasonic array method will dramatically [...] Read more.

The ultrasonic array used for thin-walled structure non-destructive inspection usually has a high central frequency so that the thickness-to-acoustic wavelength ratio is greater than 10. When the ratio is much smaller than 10, the reliability of the conventional ultrasonic array method will dramatically decrease due to the influence of the acoustic near-field. This situation is unavoidable since the available central frequency of the array transducer cannot be an arbitrarily large value. To optimize the inspection performance in this case, the testing of an ultrasonic array and the evaluation of a structure whose thickness is smaller than five-times the longitudinal wavelength are analyzed in this paper. Linear ultrasonic array methods using different combinations of wave patterns, reflection times, and coupling conditions are uniformly expressed as full matrix algorithms. Simulated and experimental full matrices of 6 mm-thick aluminum plates using a 5-MHz array transducer are captured to analyze their imaging performances and sizing abilities with respect to various defects. Analyses show that the inspection results of the wedge coupling method have a much higher signal-to-noise ratio (SNR) than the results of conventional direct contact methods. Circular defects and rectangular defects can be distinguished by comparing the imaging results of different modes. For the simulated circular defect, the diameter can be measured according to the maximum image amplitude of the defect. To simulate a rectangular defect located in the lower half of the region, the nominal length can be measured using a linear function whose input is a −6 dB drop in length of the SS-S mode image. For a real sample, the material anisotropy and complex self-reflections will decrease the SNR by about 10 dB. Full article

(This article belongs to the Special Issue Advanced Nondestructive Evaluation and Characterization of Surface)

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24 pages, 12445 KiB

Open AccessArticle

Modification of Polyethylene by RF Plasma in Different/Mixture Gases

by Aya E. Abusrafa, Salma Habib, Igor Krupa, Mabrouk Ouederni and Anton Popelka

Coatings 2019, 9(2), 145; https://doi.org/10.3390/coatings9020145 - 22 Feb 2019

Cited by 31 | Viewed by 6293

Abstract

Herein, low-density polyethylene (LDPE) films were treated using radio-frequency plasma discharge in the presence of air, nitrogen, oxygen, argon, and their mixtures to introduce new chemical functionalities. The surface properties of treated LDPE were qualitatively and quantitatively characterized using various analytical and microscopic [...] Read more.

Herein, low-density polyethylene (LDPE) films were treated using radio-frequency plasma discharge in the presence of air, nitrogen, oxygen, argon, and their mixtures to introduce new chemical functionalities. The surface properties of treated LDPE were qualitatively and quantitatively characterized using various analytical and microscopic techniques. It was found that the optimum plasma treatment for LDPE occurs in the presence of air plasma at an exposure time of 120 s and 80 W of nominal power. The plasma formed layer had tendency to increasing thickness with increasing treatment time up to 60 s using air and oxygen and even more with inert gases. An aging study of plasma-treated LDPE samples stored in ambient air or water medium revealed the partial hydrophobic recovery. Full article

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10 pages, 19495 KiB

Open AccessArticle

A Single-Ended Ultra-Thin Spherical Microbubble Based on the Improved Critical-State Pressure-Assisted Arc Discharge Method

by Wenfeng Guo, Jianxun Liu, Jinrong Liu, Gao Wang, Guanjun Wang and Mengxing Huang

Coatings 2019, 9(2), 144; https://doi.org/10.3390/coatings9020144 - 22 Feb 2019

Cited by 8 | Viewed by 3048

Abstract

Hollow core microbubble structures are good candidates for the construction of high performance whispering gallery microresonator and Fabry-Perot (FP) interference devices. In the previous reports, most of interest was just focused on the dual-ended microbubble, but not single-ended microbubble, which could be used [...] Read more.

Hollow core microbubble structures are good candidates for the construction of high performance whispering gallery microresonator and Fabry-Perot (FP) interference devices. In the previous reports, most of interest was just focused on the dual-ended microbubble, but not single-ended microbubble, which could be used for tip sensing or other special areas. The thickness, symmetry and uniformity of the single-ended microbubble in previous reports were far from idealization. Thus, a new ultra-thin single-ended spherical microbubble based on the improved critical-state pressure-assisted arc discharge method was proposed and fabricated firstly in this paper, which was fabricated simply by using a commercial fusion splicer. The improvement to former paper was using weak discharge and releasing pressure gradually during the discharging process. Thus, the negative influence of gravity towards bubble deformation was decreased, and the fabricated microbubble structure had a thin, smooth and uniform surface. By changing the arc discharge parameters and the fiber position, the wall thicknesses of the fabricated microbubble could reach the level of 2 μm or less. The fiber Fabry-Perot (FP) interference technique was also used to analyze the deformation characteristic of microbubble under difference filling pressures. Finding the ends of the microbubbles had a trend of elongation with axial compression when the filling pressure was increasing. Its sensitivity to the inner pressure of microbubble samples was about ~556 nm/MPa, the bubble wall thickness was only of about 2 μm. Besides, a high whispering gallery mode (WGM) quality factor that up to 10⁷ was realized by using this microbubble-based resonator. To explain the upper phenomenon, the microbubble was modeled and simulated with the ANSYS software. Results of this study could be useful for developing new single-ended whispering gallery mode micro-cavity structure, pressure sensors, etc. Full article

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10 pages, 8741 KiB

Open AccessArticle

The Effect of Texturing of the Surface of Concrete Substrate on the Pull-Off Strength of Epoxy Resin Coating

by Kamil Krzywiński and Łukasz Sadowski

Coatings 2019, 9(2), 143; https://doi.org/10.3390/coatings9020143 - 21 Feb 2019

Cited by 32 | Viewed by 5692

Abstract

This paper describes a study conducted to evaluate the effect of texturing of the surface of concrete substrate on the pull-off strength (f_b) of epoxy resin coating. The paper investigates a total of seventeen types of textures: after grooving, imprinting, [...] Read more.

This paper describes a study conducted to evaluate the effect of texturing of the surface of concrete substrate on the pull-off strength (f_b) of epoxy resin coating. The paper investigates a total of seventeen types of textures: after grooving, imprinting, patch grabbing and brushing. The texture of the surface of the concrete substrate was prepared during the first 15 min after pouring fresh concrete into molds. The epoxy resin coating was laid after 28 days on hardened concrete substrates. To investigate the pull-off strength of the epoxy resin coating to the concrete substrate, the pull-off method was used. The results were compared with the results obtained for a sample prepared by grinding, normative minimal pull-off strength values and the values declared by the manufacturer. During this study twelve out of fifteen tested samples achieved a pull-off strength higher than 1.50 MPa. It was found that one of the imprinting texturing methods was especially beneficial. Full article

(This article belongs to the Collection Surface and Interface Science and Engineering for the Society of the Future)

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1 pages, 135 KiB

Open AccessErratum

Erratum: Wang et al. Optimised Performance of Non-Dispersive Infrared Gas Sensors Using Multilayer Thin Film Bandpass Filters. Coatings 2018, 8, 472

by Pinggui Wang, Xiuhua Fu, Des Gibson, Lewis Fleming, Sam Ahmadzadeh, Cheng Li, Manu Muhiyudin, Shigeng Song, David Hutson, David Moodie, Calum MacGregor and Matthew Steer

Coatings 2019, 9(2), 142; https://doi.org/10.3390/coatings9020142 - 21 Feb 2019

Viewed by 2042

Abstract

The authors wish to modify the funding section as follows to this paper [...] Full article

9 pages, 2217 KiB

Open AccessArticle

Effects of Strontium-Hydroxyapatite Mediated Active Compounds from Hippocampus Kuda Bleeler (HKB) on Osteogenesis

by Chengyong Li, Qiong Yuan, Lei He, Zhong-Ji Qian, Chunxia Zhou and Pengzhi Hong

Coatings 2019, 9(2), 141; https://doi.org/10.3390/coatings9020141 - 21 Feb 2019

Cited by 3 | Viewed by 2971

Abstract

Porous hydroxyapatite as a drug carrier is very popular and has many clinical applications. However, traditional hydroxyapatite materials have limited osteogenic capacity. Therefore, the development of a new hydroxyapatite drug delivery system is essential for bone tissue engineering. In this study, the metal [...] Read more.

Porous hydroxyapatite as a drug carrier is very popular and has many clinical applications. However, traditional hydroxyapatite materials have limited osteogenic capacity. Therefore, the development of a new hydroxyapatite drug delivery system is essential for bone tissue engineering. In this study, the metal element Sr was used to replace Ca, and the SrHA microspheres were successfully prepared by hydrothermal reaction. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used to characterize SrHA (strontium-doped hydroxyapatite) microspheres obtained from hydrothermal reaction conditions. In addition, the drug utility was enhanced by loading the marine active compound 1-(5-bromo-2-hydroxy-4-methoxyphenyl)-ethanone (HKB). Furthermore, after co-culture with preosteoblasts, experiments indicated that HKB/SrHA composite microspheres had a more significant effect on the proliferation and differentiation of cells compared to pure SrHA. These HKB/SrHA composite microspheres may be applied to the drug delivery system of bone tissue repair. Full article

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16 pages, 11844 KiB

Open AccessArticle

Torsional Fretting Wear Behavior of PVD TiCN Coated CuNiAl Blade Bearing in Oil and Artificial Seawater

by Po Zhang and Jian Wang

Coatings 2019, 9(2), 140; https://doi.org/10.3390/coatings9020140 - 20 Feb 2019

Cited by 2 | Viewed by 3782

Abstract

The feasibility of alleviating torsional fretting wear of the blade bearing by preparing PVD TiCN coating was studied. The results show that the friction torque was highly influenced by the wear debris acting as the solid lubricant. The TiCN coating reduced the wear [...] Read more.

The feasibility of alleviating torsional fretting wear of the blade bearing by preparing PVD TiCN coating was studied. The results show that the friction torque was highly influenced by the wear debris acting as the solid lubricant. The TiCN coating reduced the wear volume by 97.6% and 62.3% in oil and artificial seawater, respectively, which was mainly due to an increase in surface hardness. In oil, the produced sulfates and phosphates prevent seizures between the friction pair and the worn surface was characterized by polishing wear. In artificial seawater, the wear mechanism was a combination of mechanical wear and corrosion wear. This study reveals that the TiCN coating is suitable for alleviation of fretting wear in the blade bearing. Full article

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7 pages, 2260 KiB

Open AccessArticle

Surface Modification on Cellulose Nanofibers by TiO₂ Coating for Achieving High Capture Efficiency of Nanoparticles

by Chenning Zhang, Tetsuo Uchikoshi, Izumi Ichinose and Lihong Liu

Coatings 2019, 9(2), 139; https://doi.org/10.3390/coatings9020139 - 20 Feb 2019

Cited by 13 | Viewed by 4787

Abstract

Cellulose nanofibers were modified by TiO₂ gel layer (~25 nm in thickness) via hydrolysis reaction on the surface of the cellulose nanofibers. After the TiO₂ coating, the surface charge of the nanofiber dramatically changed from negative to positive. A high efficiency [...] Read more.

Cellulose nanofibers were modified by TiO₂ gel layer (~25 nm in thickness) via hydrolysis reaction on the surface of the cellulose nanofibers. After the TiO₂ coating, the surface charge of the nanofiber dramatically changed from negative to positive. A high efficiency (~100%) of capturing negatively charged Au nanoparticles (5 nm) was successfully obtained by effectively utilizing the electrostatic interaction of surface charge between the TiO₂-coated cellulose nanofibers and Au nanoparticles. Therefore, this technique of surface modification will be potentially used in improving filtration efficiency for membrane applications. Full article

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10 pages, 3126 KiB

Open AccessArticle

Effect of Different Types of Pores on Thermal Conductivity of YSZ Thermal Barrier Coatings

by Yiling Huang, Ningning Hu, Yi Zeng, Xuemei Song, Chucheng Lin, Ziwei Liu and Jimei Zhang

Coatings 2019, 9(2), 138; https://doi.org/10.3390/coatings9020138 - 20 Feb 2019

Cited by 20 | Viewed by 3363

Abstract

Atmospheric plasma spray (APS) yttria-stabilized zirconia coatings have a complex microstructure with a variety of pores that significantly reduce the thermal conductivity. APS thermal barrier coatings (TBCs) with a similar monoclinic phase were prepared. The pore sizes and distributions of the coatings were [...] Read more.

Atmospheric plasma spray (APS) yttria-stabilized zirconia coatings have a complex microstructure with a variety of pores that significantly reduce the thermal conductivity. APS thermal barrier coatings (TBCs) with a similar monoclinic phase were prepared. The pore sizes and distributions of the coatings were obtained by scanning their cross-section via SEM; the scanned areas were over 1 mm × 2 mm and more than 23,000 pores for each coating were analyzed. Multiple linear regression was used to analyze the porosity data and then to determine the quantitative relationship between different types of pores and thermal conductivity. Results revealed that the different pores have different effects on decreasing the thermal conductivity. The small, vertical pores have the biggest effect, while the horizontal pores also play a significant role in decreasing the thermal conductivity. Full article

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27 pages, 3518 KiB

Open AccessFeature PaperReview

Transparent p-Type Semiconductors: Copper-Based Oxides and Oxychalcogenides

by Nengduo Zhang, Jian Sun and Hao Gong

Coatings 2019, 9(2), 137; https://doi.org/10.3390/coatings9020137 - 20 Feb 2019

Cited by 58 | Viewed by 8885

Abstract

While p-type transparent conducting materials (TCMs) are crucial for many optoelectronic applications, their performance is still not satisfactory. This has impeded the development of many devices such as photovoltaics, sensors, and transparent electronics. Among the various p-type TCMs proposed so far, Cu-based oxides [...] Read more.

While p-type transparent conducting materials (TCMs) are crucial for many optoelectronic applications, their performance is still not satisfactory. This has impeded the development of many devices such as photovoltaics, sensors, and transparent electronics. Among the various p-type TCMs proposed so far, Cu-based oxides and oxychalcogenides have demonstrated promising results in terms of their optical and electrical properties. Hence, they are the focus of this current review. Their basic material properties, including their crystal structures, conduction mechanisms, and electronic structures will be covered, as well as their device applications. Also, the development of performance enhancement strategies including doping/co-doping, annealing, and other innovative ways to improve conductivity will be discussed in detail. Full article

(This article belongs to the Special Issue Thin Films for Electronic Applications)

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9 pages, 3368 KiB

Open AccessArticle

The Properties of Zn-Doped AlSb Thin Films Prepared by Pulsed Laser Deposition

by Ping Tang, Weimin Wang, Bing Li, Lianghuan Feng and Guanggen Zeng

Coatings 2019, 9(2), 136; https://doi.org/10.3390/coatings9020136 - 20 Feb 2019

Cited by 11 | Viewed by 3158

Abstract

Aluminum antimony (AlSb) is a promising photovoltaic material with a band gap of about 1.62 eV. However, AlSb is highly deliquescent and not stable, which has brought great difficulties to the applications. Based on the above situation, there are two purposes for preparing [...] Read more.

Aluminum antimony (AlSb) is a promising photovoltaic material with a band gap of about 1.62 eV. However, AlSb is highly deliquescent and not stable, which has brought great difficulties to the applications. Based on the above situation, there are two purposes for preparing our Zn-doped AlSb (AlSb:Zn) thin films: One is to make P-type AlSb and the other is to find a way to suppress the deliquescence of AlSb. The AlSb:Zn thin films were prepared on glass substrates at different substrate temperatures by using the pulsed laser deposition (PLD) method. The structural, surface morphological, optical, and electrical properties of AlSb:Zn films were investigated. The crystallization of AlSb:Zn thin films was enhanced and the electrical resistivity decreased as the substrate temperature increased. The scanning electron microscopy (SEM) images indicated that the grain sizes became bigger as the substrate temperatures increased. The Raman vibration mode AlSb:Zn films were located at ~107 and ~142 cm⁻¹ and the intensity of Raman peaks was stronger at higher substrate temperatures. In the experiment, a reduced band gap (1.4 eV) of the AlSb:Zn thin film was observed compared to the undoped AlSb films, which were more suitable for thin-film solar cells. Zn doping could reduce the deliquescent speed of AlSb thin films. The fabricated heterojunction device showed the good rectification behavior, which indicated the PN junction formation. The obvious photovoltaic effect has been observed in an FTO/ZnS/AlSb:Zn/Au device. Full article

(This article belongs to the Special Issue Electrochromic Thin Films and Devices)

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12 pages, 2788 KiB

Open AccessArticle

Corrosiveness of Palm Biodiesel in Gray Cast Iron Coated by Thermoreactive Diffusion Vanadium Carbide (VC) Coating

by Ariel Amaya, Oscar Piamba and Jhon Olaya

Coatings 2019, 9(2), 135; https://doi.org/10.3390/coatings9020135 - 20 Feb 2019

Cited by 9 | Viewed by 3425

Abstract

Palm biodiesel is a currently used biofuel, principally as an additive or substitute of diesel fuel in vehicular internal combustion engines. In the present work, vanadium carbide (VC) coatings were deposited on gray cast iron (GCI) using the thermoreactive diffusion process (TRD) to [...] Read more.

Palm biodiesel is a currently used biofuel, principally as an additive or substitute of diesel fuel in vehicular internal combustion engines. In the present work, vanadium carbide (VC) coatings were deposited on gray cast iron (GCI) using the thermoreactive diffusion process (TRD) to evaluate the corrosiveness of palm biodiesel and compare it with gray cast iron corrosion behavior. VC coated and uncoated gray cast iron samples were tested by immersion corrosion tests (291 K and 313 K), cyclic oxidation test (CO), and the electrochemical impedance spectrometry test (EIS). The corrosion test showed the reduction of the corrosion rate for the VC coating when compared to gray cast iron. EIS tests of coated samples showed higher values of polarization resistance when compared with uncoated gray cast iron samples. Results confirmed that while biodiesel was more corrosive than diesel on both coated and uncoated gray cast iron, the VC coating was efficient in protecting the substrate exposed to both fuels. Full article

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13 pages, 3818 KiB

Open AccessArticle

Argon Plasma Surface Modified Porcine Bone Substitute Improved Osteoblast-Like Cell Behavior

by Cheuk Sing Choy, Eisner Salamanca, Pei Ying Lin, Haw-Ming Huang, Nai-Chia Teng, Yu-Hwa Pan and Wei-Jen Chang

Coatings 2019, 9(2), 134; https://doi.org/10.3390/coatings9020134 - 19 Feb 2019

Cited by 2 | Viewed by 3299

Abstract

Low-temperature plasma-treated porcine grafts (PGPT) may be an effective means for treating demanding osseous defects and enhance our understanding of plasma-tissue engineering. We chemically characterized porcine grafts under low-temperature Argon plasma treatment (CAP) and evaluated their biocompatibility in-vitro. Our results showed that PGPT [...] Read more.

Low-temperature plasma-treated porcine grafts (PGPT) may be an effective means for treating demanding osseous defects and enhance our understanding of plasma-tissue engineering. We chemically characterized porcine grafts under low-temperature Argon plasma treatment (CAP) and evaluated their biocompatibility in-vitro. Our results showed that PGPT did not differ in roughness, dominant crystalline phases, absorption peaks corresponding to phosphate band peaks, or micro-meso pore size, compared to non-treated porcine grafts. The PGPT Ca/P ratio was 2.16; whereas the porcine control ratio was 2.04 (p < 0.05). PGPT’s [C 1s], [P 2p] and [Ca 2p] values were 24.3%, 5.6% and 11.0%, respectively, indicating that PGPT was an apatite without another crystalline phase. Cell viability and alkaline phosphatase assays revealed enhanced proliferation and osteoblastic differentiation for the cells cultivated in the PGPT media after 5 days (p < 0.05). The cells cultured in PGPT medium had higher bone sialoprotein and osteocalcin relative mRNA expression compared to cells cultured in non-treated porcine grafts (p < 0.05). CAP treatment of porcine particles did not modify the biomaterial’s surface and improved the proliferation and differentiation of osteoblast-like cells. Full article

(This article belongs to the Special Issue Surface Chemical Modification)

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30 pages, 14107 KiB

Open AccessReview

Ångström-Scale, Atomically Thin 2D Materials for Corrosion Mitigation and Passivation

by Md Rubayat-E Tanjil, Yunjo Jeong, Zhewen Yin, Wyatt Panaccione and Michael Cai Wang

Coatings 2019, 9(2), 133; https://doi.org/10.3390/coatings9020133 - 19 Feb 2019

Cited by 21 | Viewed by 15338

Abstract

Metal deterioration via corrosion is a ubiquitous and persistent problem. Ångström-scale, atomically thin 2D materials are promising candidates for effective, robust, and economical corrosion passivation coatings due to their ultimate thinness and excellent mechanical and electrical properties. This review focuses on elucidating the [...] Read more.

Metal deterioration via corrosion is a ubiquitous and persistent problem. Ångström-scale, atomically thin 2D materials are promising candidates for effective, robust, and economical corrosion passivation coatings due to their ultimate thinness and excellent mechanical and electrical properties. This review focuses on elucidating the mechanism of 2D materials in corrosion mitigation and passivation related to their physicochemical properties and variations, such as defects, out-of-plane deformations, interfacial states, temporal and thickness variations, etc. In addition, this review discusses recent progress and developments of 2D material coatings for corrosion mitigation and passivation as well as the significant challenges to overcome in the future. Full article

(This article belongs to the Special Issue Corrosion Characterization and Surface Analysis of Metallic Materials)

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16 pages, 2791 KiB

Open AccessArticle

Method of Stabilizing Heavily Spalted Big Leaf Maple as a Decorative Coating Veneer Layer for Engineered Wood Flooring

by Diego Rodrigues de Oliveira, Claudia C. Andersen, Sarath M. Vega Gutierrez, Frederick A. Kamke and Seri C. Robinson

Coatings 2019, 9(2), 132; https://doi.org/10.3390/coatings9020132 - 19 Feb 2019

Cited by 4 | Viewed by 3151

Abstract

Spalted wood, wood colored by fungi, has been popular in woodcraft for centuries. Most spalted wood, however, is found in an advanced state of decay and cannot be utilized. This project describes the use of viscoelastic thermal compression (VTC) to investigate the potential [...] Read more.

Spalted wood, wood colored by fungi, has been popular in woodcraft for centuries. Most spalted wood, however, is found in an advanced state of decay and cannot be utilized. This project describes the use of viscoelastic thermal compression (VTC) to investigate the potential increase in spalted woods’ strength and stiffness, with the main objective of converting so-called “punky” wood into the top layer (veneer layer or “coating”) on commercial flooring. Spalted Acer macrophyllum logs were cut into veneers of size 7 mm × 7.8 cm × 25 cm and were then VTC-treated at 150 °C and 50 psi for 11.5 min. Statistical analysis on the mixed linear models showed significant increases for both the density and hardness of spalted wood (p < 0.0001). Density and Brinell hardness increased by 84% and 209%, respectively. FTIR analysis revealed that the wood polymers present in spalted wood were more susceptible to degradation imposed by the heat of the VTC treatment compared to sound wood. Additionally, the color analysis of the wood specimens showed statistically significant changes in color after the VTC treatment (p < 0.0001), which turned the wood surface darker and redder. The use of the VTC technology to transform spalted wood into wood flooring is viable. However, when exposed to moisture, the VTC-treated spalted wood showed a high percentage of set recovery (78%), which was significantly different from the set recovery of the sound wood (71%, p = 0.004). Successful use of VTC-treated spalted wood for flooring will require addressing of the swelling issue, and additional studies are needed to fully characterize the anatomy of VTC-treated spalted wood. Full article

(This article belongs to the Special Issue Additives and Pre-treatments to Enhance the Performance of Coatings on Wood)

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11 pages, 8085 KiB

Open AccessArticle

Laser Surface Blasting of Granite Stones Using a Laser Scanning System

by Joaquín Penide, Jesús del Val, Antonio Riveiro, Ramón Soto, Rafael Comesaña, Félix Quintero, Mohamed Boutinguiza, Fernando Lusquiños and Juan Pou

Coatings 2019, 9(2), 131; https://doi.org/10.3390/coatings9020131 - 19 Feb 2019

Cited by 5 | Viewed by 4242

Abstract

Granite stones are the most abundant rock of the crust. Due to their beauty, durability, and virtually zero maintenance, they have been used widely since ancient times in all types of construction, as a structural or decorative element. Commonly, this material is used [...] Read more.

Granite stones are the most abundant rock of the crust. Due to their beauty, durability, and virtually zero maintenance, they have been used widely since ancient times in all types of construction, as a structural or decorative element. Commonly, this material is used with a polished finishing, but there has been an increased interest in giving it a rustic aspect, mainly for decorative or functional reasons, e.g., to reduce slipping. Rough surfaces are usually produced by means of bush hammering, but this is an extremely noisy and inefficient process. In this work we have explored the capabilities and limits of a laser blasting process assisted by a scanning system in order to produce precise and controllable roughness on two varieties of granite plates. It was found that laser blasting of thin granite tiles can be accomplished with processing widths up to 250 mm at medium-low laser power, obtaining a rustic aspect suitable for use in façades, paving, or flooring. Moreover, laser scanner systems are capable of enhancing the productivity of this process up to ten times greater than that found in previous works. Full article

(This article belongs to the Special Issue Surface Treatment by Laser-Assisted Techniques)

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11 pages, 4522 KiB

Open AccessArticle

Fabrication of Cu₂ZnSnS₄ Thin Films Based on Facile Nanocrystals-Printing Approach with Rapid Thermal Annealing (RTA) Process

by Jin Chen, Fengchao Wang, Bobo Yang, Xiaogai Peng, Qinmiao Chen, Jun Zou and Xiaoming Dou

Coatings 2019, 9(2), 130; https://doi.org/10.3390/coatings9020130 - 19 Feb 2019

Cited by 19 | Viewed by 2997

Abstract

In the current study, Cu₂ZnSnS₄ (CZTS) thin film was successfully fabricated by the facile nanocrystals (NCs)-printing approach combined with rapid thermal annealing (RTA) process. Firstly, the CZTS NCs were synthesized by a thermal solution method and the possible formation mechanism [...] Read more.

In the current study, Cu₂ZnSnS₄ (CZTS) thin film was successfully fabricated by the facile nanocrystals (NCs)-printing approach combined with rapid thermal annealing (RTA) process. Firstly, the CZTS NCs were synthesized by a thermal solution method and the possible formation mechanism was analyzed briefly. Then the influences of RTA toleration temperature and duration time on the various properties of as-printed thin films were examined via XRD, Raman, FE-SEM, UV-vis-IR spectroscopy, EDS and XPS treatments in detail. As observed, the RTA factors of temperature and time had significant impacts on the structure and morphology of as-prepared thin films, while there were no obvious effects on the band gap energy in studied conditions. The results showed that the obtained thin film at optimal RTA conditions of (600 °C, 20 min) featured a kesterite structure in pure phase and an irregular morphology consisting of large grains. Moreover, the satisfactory composition of a Cu-poor, Zn-rich state and an ideal band gap energy of 1.4 eV suggests that as-fabricated CZTS thin film is a suitable light-absorbing layer candidate for the application in thin film solar cells. Full article

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14 pages, 1850 KiB

Open AccessReview

Research Status and Prospect of Friction Stir Processing Technology

by Kan Li, Xuemei Liu and Yi Zhao

Coatings 2019, 9(2), 129; https://doi.org/10.3390/coatings9020129 - 19 Feb 2019

Cited by 63 | Viewed by 8077

Abstract

Friction stir processing (FSP) is a novel solid-phase processing technique that is derived from friction stir welding (FSW). The microstructure of the base metal can be modified with the friction heat and stir function during processing. It can be used to fabricate surface [...] Read more.

Friction stir processing (FSP) is a novel solid-phase processing technique that is derived from friction stir welding (FSW). The microstructure of the base metal can be modified with the friction heat and stir function during processing. It can be used to fabricate surface composites and in situ composites by adding reinforced particles into the metal matrix via FSP. Friction stir processing can significantly improve the hardness, wear resistance, ductility, etc., while preventing defects caused by material melting. It is an ideal material processing technology and has good prospects in the field of superplastic materials and for the preparation of metal matrix composites. This paper reviews research developments into the principle, process, and applications of FSP technology as well as its future research directions and development prospects. Full article

(This article belongs to the Special Issue Recent Advances in Friction Stir Processed Coatings)

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10 pages, 3367 KiB

Open AccessArticle

A Deep Insight into the Electronic Properties of CIGS Modules with Monolithic Interconnects Based on 2D Simulations with TCAD

by Ricardo Vidal Lorbada, Thomas Walter, David Fuertes Marrón, Tetiana Lavrenko and Dennis Muecke

Coatings 2019, 9(2), 128; https://doi.org/10.3390/coatings9020128 - 19 Feb 2019

Cited by 2 | Viewed by 3760

Abstract

The aim of this work is to provide an insight into the impact of the P1 shunt on the performance of ZnO/CdS/Cu(In,Ga)Se₂/Mo modules with monolithic interconnects. The P1 scribe is a pattern that separates the back contact of two adjacent cells [...] Read more.

The aim of this work is to provide an insight into the impact of the P1 shunt on the performance of ZnO/CdS/Cu(In,Ga)Se₂/Mo modules with monolithic interconnects. The P1 scribe is a pattern that separates the back contact of two adjacent cells and is filled with Cu(In,Ga)Se₂ (CIGS). This scribe introduces a shunt that can affect significantly the behavior of the device, especially under weak light conditions. Based on 2D numerical simulations performed with TCAD, we postulate a mechanism that affects the current flow through the P1 shunt. This mechanism is similar to that of a junction field effect transistor device with a p-type channel, in which the current flow can be modulated by varying the thickness of the channel and the doping concentration. The results of these simulations suggest that expanding the space charge region (SCR) into P1 reduces the shunt conductance in this path significantly, thus decreasing the current flow through it. The presented simulations demonstrate that two fabrication parameters have a direct influence on the extension of the SCR, which are the thickness of the absorber layer and its acceptor concentration. Full article

(This article belongs to the Special Issue Advanced Thin Film Materials for Photovoltaic Applications)

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10 pages, 3252 KiB

Open AccessArticle

Tridoped TiO₂ Composite Films for Improved Photocatalytic Activities

by Li-Zhu Zhao, Ke Han, Fang Li and Ming-Ming Yao

Coatings 2019, 9(2), 127; https://doi.org/10.3390/coatings9020127 - 19 Feb 2019

Cited by 5 | Viewed by 3018

Abstract

The Fe/B/F tridoped TiO₂-ZnO composite films attached to glass substrates were prepared via a simple sol–gel method. We appraised all samples’ photocatalytic activities by the degradation of methyl green and formaldehyde solutions. The samples were characterized by photoluminescence (PL) spectra, UV-Vis [...] Read more.

The Fe/B/F tridoped TiO₂-ZnO composite films attached to glass substrates were prepared via a simple sol–gel method. We appraised all samples’ photocatalytic activities by the degradation of methyl green and formaldehyde solutions. The samples were characterized by photoluminescence (PL) spectra, UV-Vis diffraction reflectance absorption spectra (DRS), X-ray diffraction (XRD), differential thermal analysis-thermogravimetry (DTA-TG), field emission scanning electron microscopy (FE-SEM) equipped with energy-dispersive spectroscopy (EDS), and Brunner–Emmet–Teller (BET) measurements. According to the results of DRS and PL spectroscopy, the multi-modification could not only enhance visible light absorption intensity, but also decrease the recombination rate of photo-generated electron-hole pairs. XRD results revealed that the sample was mainly in anatase crystal type. FE-SEM results shown that the sample had fewer particle aggregates and almost no cracks. The specific surface area of the Fe/B/F tridoped TiO₂-ZnO was 104.9 m²·g⁻¹, while that of the pure TiO₂ was 84.0 m²·g⁻¹. Compared to pure TiO₂ and TiO₂-ZnO, the Fe/B/F tridoped TiO₂-ZnO composite film had the highest photocatalytic activity due to their synergies. Full article

(This article belongs to the Special Issue Photocatalytic Thin Films)

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15 pages, 1631 KiB

Open AccessFeature PaperArticle

Technical and Economic Criteria to Select Pavement Surfaces of Port Handling Plants

by Paola Di Mascio, Giuseppe Loprencipe and Laura Moretti

Coatings 2019, 9(2), 126; https://doi.org/10.3390/coatings9020126 - 18 Feb 2019

Cited by 12 | Viewed by 3643

Abstract

A port is an intermodal system in which many logistics activities requiring properly constructed areas occur. The large extension of these areas poses a major problem in choosing materials with technical and economic implications. Choice and design of pavements are directly related to [...] Read more.

A port is an intermodal system in which many logistics activities requiring properly constructed areas occur. The large extension of these areas poses a major problem in choosing materials with technical and economic implications. Choice and design of pavements are directly related to the port handling systems and procedures for the disposal of the cargo units. The paper presents the design and verification procedures for three equivalent pavements for a handling pavement in an Italian medium-sized port trafficked by reach stackers moving containers. An asphalt pavement, a concrete pavement, and a concrete block pavement have been considered during the 20-year service life. Empirical and analytical methods have been adopted to design and verify the pavements. The structures have been examined in terms of economic concerns during the overall service life, considering both construction and maintenance costs, in order to determine the most cost-effective option. The results demonstrate the inappropriateness of asphalt pavement, in the examined case, from a construction costs point of view. Furthermore, the overall discounted costs show an inversion of convenience between block concrete pavement and cast in situ concrete: the latter is the cheaper solution. The proposed methodology can balance often conflicting objectives in matters of durability and funds management, providing answers to a complex topic. Full article

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8 pages, 2492 KiB

Open AccessArticle

Surface Structuring of Diamond-Like Carbon Films by Chemical Etching of Zinc Inclusions

by Ruriko Hatada, Stefan Flege, Berthold Rimmler, Christian Dietz, Wolfgang Ensinger and Koumei Baba

Coatings 2019, 9(2), 125; https://doi.org/10.3390/coatings9020125 - 18 Feb 2019

Cited by 5 | Viewed by 4888

Abstract

A diamond-like carbon (DLC) film with a nanostructured surface can be produced in a two-step process. At first, a metal-containing DLC film is deposited. Here, the combination of plasma source ion implantation using a hydrocarbon gas and magnetron sputtering of a zinc target [...] Read more.

A diamond-like carbon (DLC) film with a nanostructured surface can be produced in a two-step process. At first, a metal-containing DLC film is deposited. Here, the combination of plasma source ion implantation using a hydrocarbon gas and magnetron sputtering of a zinc target was used. Next, the metal particles within the surface are dissolved by an etchant (HNO₃:H₂O solution in this case). Since Zn particles in the surface of Zn-DLC films have a diameter of 100–200 nm, the resulting surface structures possess the same dimensions, thus covering a range that is accessible neither by mask deposition techniques nor by etching of other metal-containing DLC films, such as Cu-DLC. The surface morphology of the etched Zn-DLC films depends on the initial metal content of the film. With a low zinc concentration of about 10 at.%, separate holes are produced within the surface. Higher zinc concentrations (40 at.% or above) lead to a surface with an intrinsic roughness. Full article

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13 pages, 3376 KiB

Open AccessArticle

Coating Sand with New Hydrophobic and Superhydrophobic Silica/Paraffin Wax Nanocapsules for Desert Water Storage and Transportation

by Ayman M. Atta, Mahmood M. S. Abdullah, Hamad A. Al-Lohedan and Nermen H. Mohamed

Coatings 2019, 9(2), 124; https://doi.org/10.3390/coatings9020124 - 17 Feb 2019

Cited by 18 | Viewed by 5670

Abstract

Paraffin wax emulsions have gained immense attention as a cheap, environment-friendly, and aroma-free material for preparing superhydrophobic coatings. In this work, paraffin wax (PWs) capsules consisting of hydrophobic silica nanoparticles were used for coating desert sand. Different types of the hydrophobic silica nanoparticles, [...] Read more.

Paraffin wax emulsions have gained immense attention as a cheap, environment-friendly, and aroma-free material for preparing superhydrophobic coatings. In this work, paraffin wax (PWs) capsules consisting of hydrophobic silica nanoparticles were used for coating desert sand. Different types of the hydrophobic silica nanoparticles, modified with new oleylamino- and oleylamide silane precursors, were prepared in the presence and absence of paraffin waxes. The particle sizes, surface charges, thermal stability, surface morphologies, and wetting characteristics of these nanoparticles were investigated. The combination of these superhydrophobic silica nanoparticles and desert sand, showed excellent water repellency; stable water droplets remained on the sand surface, without any wetting or permeation. Furthermore, the mixing of the superhydrophobic sand with untreated sand (mixing ratio 1:10 wt %), with a thickness of 2 cm, sustained a great water-holding capacity with a water column height of 35 cm. The good thermal stability of the PWs capsules containing hydrophobic silica nanoparticles, along with their good water-holding capacity, make them potential candidates for developing superhydrophobic sand for desert water storage and transportation. Full article

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15 pages, 4387 KiB

Open AccessArticle

Functional Performance of Stone Mastic Asphalt Pavements in Spain: Acoustic Assessment

by Víctor F. Vázquez, Fernando Terán, Jeanne Luong and Santiago E. Paje

Coatings 2019, 9(2), 123; https://doi.org/10.3390/coatings9020123 - 16 Feb 2019

Cited by 12 | Viewed by 3697

Abstract

Environmental noise is one of the problems modern societies face today. Traffic noise, especially the noise produced from tire/pavement interaction, plays a main role in environmental noise. Pavement rehabilitation with new bituminous mixtures is a good option for combatting noise pollution in urban [...] Read more.

Environmental noise is one of the problems modern societies face today. Traffic noise, especially the noise produced from tire/pavement interaction, plays a main role in environmental noise. Pavement rehabilitation with new bituminous mixtures is a good option for combatting noise pollution in urban areas. This paper studies the functional performance of two bituminous mixtures of stone mastic asphalt (SMA), fabricated with the same polymer modified binder, but with different maximum aggregate size (MAS) (SMA11 and SMA16). The acoustic absorption, the dynamic stiffness, the surface texture and the tire/pavement noise were assessed. The bituminous mixture type SMA16 has higher texture levels at nearly every depicted wavelength of the texture spectra. This characteristic may lead to its higher average tire/pavement sound level compared to the mixture SMA11. The influence of each texture wavelength on the different frequency bands of the tire/pavement noise spectrum was studied, however, this relation is not a simple matter. This paper also presents low-noise pavement labeling methodology (LNP labeling^LA²IC). The mixtures SMA11 and SMA16 are labeled at 50 and 80 km/h. An acoustic label is a valuable tool for construction companies and urban planners to use in order to define the best option against noise when pavement rehabilitation must be carried out. Full article

(This article belongs to the Collection Pavement Surface Coatings)

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19 pages, 794 KiB

Open AccessArticle

Modeling Self-Healing Mechanisms in Coatings: Approaches and Perspectives

by Etelvina Javierre

Coatings 2019, 9(2), 122; https://doi.org/10.3390/coatings9020122 - 15 Feb 2019

Cited by 16 | Viewed by 3346

Abstract

There is a wide range of self-healing mechanisms that provide the recovery of specific functionalities in coatings. Moreover, it is well known that computational simulation is a complementary tool that can help in the optimization and cost reduction of the experimental development of [...] Read more.

There is a wide range of self-healing mechanisms that provide the recovery of specific functionalities in coatings. Moreover, it is well known that computational simulation is a complementary tool that can help in the optimization and cost reduction of the experimental development of materials. This work critically discusses the current status of the models that are of interest for the advance of self-healing coatings, and proposes future paths of improvement. Full article

(This article belongs to the Special Issue Progress in Self-Healing Coatings)

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13 pages, 1790 KiB

Open AccessArticle

Evaluation of the Impacts of Four Weathering Methods on Two Acrylic Paints: Showcasing Distinctions and Particularities

by Antoine Cogulet, Pierre Blanchet and Véronic Landry

Coatings 2019, 9(2), 121; https://doi.org/10.3390/coatings9020121 - 15 Feb 2019

Cited by 24 | Viewed by 4290

Abstract

Two commercial waterborne wood acrylic paints were applied to wood samples and the weathering resistance of samples was tested using four different weathering methods: outdoor exposure in Arizona (USA), Florida (USA), and the province of Quebec (Canada), and accelerated weathering in a QUV [...] Read more.

Two commercial waterborne wood acrylic paints were applied to wood samples and the weathering resistance of samples was tested using four different weathering methods: outdoor exposure in Arizona (USA), Florida (USA), and the province of Quebec (Canada), and accelerated weathering in a QUV (fluorescent) weatherometer. Degradation was characterised by colorimetric and FTIR analyses. FTIR confirmed the importance of paint composition in the resistance of samples to weathering. Polymer sensitivity to UV radiation was clearly evident. An interpretation of discoloration in terms of either the energy received by the samples or the length of exposure is presented. Strong differences existed between the four weathering methods. Particularities of each method are discussed and recommendations regarding their application for effective testing are proposed. Overall, in addition to accelerated weathering tests, we conclude that it is necessary to test paints in an end-use environment for accurate assessment of their likely performance. This study confirms the multifactorial aspect of the weathering process. Full article

(This article belongs to the Special Issue Additives and Pre-treatments to Enhance the Performance of Coatings on Wood)

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11 pages, 3032 KiB

Open AccessEditor’s ChoiceArticle

Thermoelectric Properties of Thin Films of Germanium-Gold Alloy Obtained by Magnetron Sputtering

by Damian Nowak, Marta Turkiewicz and Natalia Solnica

Coatings 2019, 9(2), 120; https://doi.org/10.3390/coatings9020120 - 15 Feb 2019

Cited by 6 | Viewed by 4140

Abstract

In this paper, the electric and thermoelectric properties of thin films of germanium–gold alloy (Ge–Au) are discussed in terms of choosing the optimal deposition process and post-processing conditions to obtain Ge–Au layers with the best thermoelectric parameters. Thin films were fabricated by magnetron [...] Read more.

In this paper, the electric and thermoelectric properties of thin films of germanium–gold alloy (Ge–Au) are discussed in terms of choosing the optimal deposition process and post-processing conditions to obtain Ge–Au layers with the best thermoelectric parameters. Thin films were fabricated by magnetron sputtering using the Ge–Au alloy target onto glass substrates at two various conditions; during one of the sputtering processes, the external substrate bias voltage (U_b = −150 V) was used. After deposition thin films were annealed in the atmosphere of N₂ at various temperatures (473, 523 and 573 K) to investigate the influence of annealing temperature on the electric and thermoelectric properties of films. Afterwards, the thermocouples were created by deposition of the NiCrSi/Ag contact pads onto Ge–Au films. In this work, particular attention has been paid to thermoelectric properties of fabricated thin films—the thermoelectric voltage, Seebeck coefficient, power factor PF and dimensionless figure of merit ZT were determined. Full article

(This article belongs to the Special Issue Novel Thin Film Materials for Thermoelectric Applications)

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Coatings, Volume 9, Issue 2 (February 2019) – 87 articles

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