Surface Chemical Modification

A special issue of Coatings (ISSN 2079-6412). This special issue belongs to the section "Surface Characterization, Deposition and Modification".

Deadline for manuscript submissions: closed (28 February 2021) | Viewed by 87455

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Department of Mechanical Engineering, University of Canterbury, Kirkwood Ave., Christchurch 8140, New Zealand
Interests: intelligent design and manufacturing; spiking neural network; bioprinting; neuroengineering
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Dear Colleagues,

We would like to invite you to submit your work to this Special Issue on "Surface Chemical Modification". Surface chemical modification is the modification of the surface of a material by introducing different chemical properties different from the ones originally found on the surface. With the development of engineering and science in the micro/nano scale, the precise control of surface chemical properties is becoming increasingly critical in both fundamental scientific researches and applied engineering applications, such as biology, energy, environment, etc. Vast scientific and technological progress has been achieved on this topic by universities and research institutes all around the world. This progress has been supported by the industrial development of novel characterization and deposition tools. The aim of this Special Issue is to present the latest experimental and theoretical developments in the field, through a combination of original research papers and review articles from leading groups around the world.

Prof. Dr. Yilei Zhang
Guest Editor

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Keywords

  • Two-dimensional nanomaterials

  • Nanoparticles

  • Microfluidic devices

  • Reinforcements

  • Biology

  • Energy

  • Environment

  • Natural materials

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Published Papers (14 papers)

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Research

Jump to: Review

12 pages, 2326 KiB  
Article
Optical Evidence for the Assembly of Sensors Based on Reduced Graphene Oxide and Polydiphenylamine for the Detection of Epidermal Growth Factor Receptor
by Mihaela Baibarac, Monica Daescu and Szilard N. Fejer
Coatings 2021, 11(2), 258; https://doi.org/10.3390/coatings11020258 - 23 Feb 2021
Cited by 2 | Viewed by 2191
Abstract
Using Raman scattering and FTIR spectroscopy, new optical evidence for the assembly of sensors based on reduced graphene oxide (RGO) and polydiphenylamine (PDPA) for the electrochemical detection of the epidermal growth factor receptor (EGFR) are reported. The assembly process of the RGO sheets [...] Read more.
Using Raman scattering and FTIR spectroscopy, new optical evidence for the assembly of sensors based on reduced graphene oxide (RGO) and polydiphenylamine (PDPA) for the electrochemical detection of the epidermal growth factor receptor (EGFR) are reported. The assembly process of the RGO sheets electrochemical functionalized with PDPA involves the chemical adsorption of 1,4-phenylene diisothiocyanate (PDITC), followed by an incubation with protein G in phosphate buffer (PB) solution and after that the interaction with EGFR antibodies solution. Taking into account the changes reported by Raman scattering and FTIR spectroscopy, a chemical mechanism of the assembling process for this sensor is proposed. The preliminary testing of the electrochemical activity of the sensors based on RGO and PDPA was reported by cyclic voltammetry. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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21 pages, 11418 KiB  
Article
Easy and Fast Fabrication of Self-Cleaning and Anti-Icing Perfluoroalkyl Silane Film on Aluminium
by Peter Rodič, Barbara Kapun, Matjaž Panjan and Ingrid Milošev
Coatings 2020, 10(3), 234; https://doi.org/10.3390/coatings10030234 - 4 Mar 2020
Cited by 28 | Viewed by 5573
Abstract
A combination of the chemical etching process in FeCl3 solution and chemical surface grafting by immersion in ethanol solution containing 1H,1H,2H,2H-perfluorodecyltriethoxysilane is a viable route to achieve a hierarchical surface topography and chemical bonding of silane molecules on an aluminium surface leading [...] Read more.
A combination of the chemical etching process in FeCl3 solution and chemical surface grafting by immersion in ethanol solution containing 1H,1H,2H,2H-perfluorodecyltriethoxysilane is a viable route to achieve a hierarchical surface topography and chemical bonding of silane molecules on an aluminium surface leading to (super)hydrophobic characteristics. Characterisation of untreated and treated aluminium surfaces was carried out using contact profilometry, optical tensiometry, scanning electron microscopy coupled with energy-dispersive spectroscopy and X-ray photoelectron spectroscopy to define the surface topography, wettability, morphology and surface composition. Additionally, the dynamic characteristics were evaluated to define bouncing and the self-cleaning effect. A thermal infrared camera was employed to evaluate anti-icing properties. The micro/nano-structured etched aluminium surface grafted with perfluoroalkyl silane film showed excellent superhydrophobicity and bounce dynamics in water droplet tests. The superhydrophobic aluminium surface exhibited the efficient self-cleaning ability of solid pollutants as well as improved anti-icing performance with melting delay. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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11 pages, 2349 KiB  
Article
Chemical Modification of Novel Glycosidases from Lactobacillus plantarum Using Hyaluronic Acid: Effects on High Specificity against 6-Phosphate Glucopyranoside
by Carlos Perez-Rizquez, David Lopez-Tejedor, Laura Plaza-Vinuesa, Blanca de las Rivas, Rosario Muñoz, Jose Cumella and Jose M. Palomo
Coatings 2019, 9(5), 311; https://doi.org/10.3390/coatings9050311 - 9 May 2019
Cited by 6 | Viewed by 3237
Abstract
Three novel glycosidases produced from Lactobacillus plantarum, so called Lp_0440, Lp_2777, and Lp_3525, were isolated and overexpressed on Escherichia coli containing a His-tag for specific purification. Their specific activity was evaluated against the hydrolysis of p-nitrophenylglycosides and p-nitrophenyl-6-phosphate glycosides (glucose [...] Read more.
Three novel glycosidases produced from Lactobacillus plantarum, so called Lp_0440, Lp_2777, and Lp_3525, were isolated and overexpressed on Escherichia coli containing a His-tag for specific purification. Their specific activity was evaluated against the hydrolysis of p-nitrophenylglycosides and p-nitrophenyl-6-phosphate glycosides (glucose and galactose) at pH 7. All three were modified with hyaluronic acid (HA) following two strategies: A simple coating by direct incubation at alkaline pH or direct chemical modification at pH 6.8 through preactivation of HA with carbodiimide (EDC) and N-hydroxysuccinimide (NHS) at pH 4.8. The modifications exhibited important effect on enzyme activity and specificity against different glycopyranosides in the three cases. Physical modification showed a radical decrease in specific activity on all glycosidases, without any significant change in enzyme specificity toward monosaccharide (glucose or galactose) or glycoside (C-6 position free or phosphorylated). However, the surface covalent modification of the enzymes showed very interesting results. The glycosidase Lp_0440 showed low glycoside specificity at 25 °C, showing the same activity against p-nitrophenyl-glucopyranoside (pNP-Glu) or p-nitrophenyl-6-phosphate glucopyranoside (pNP-6P-Glu). However, the conjugated cHA-Lp_0440 showed a clear increase in the specificity towards the pNP-Glu and no activity against pNP-6P-Glu. The other two glycosidases (Lp_2777 and Lp_3525) showed high specificity towards pNP-6P-glycosides, especially to the glucose derivative. The HA covalent modification of Lp_3525 (cHA-Lp_3525) generated an enzyme completely specific against the pNP-6P-Glu (phosphoglycosidase) maintaining more than 80% of the activity after chemical modification. When the temperature was increased, an alteration of selectivity was observed. Lp_0440 and cHA-Lp_0440 only showed activity against p-nitrophenyl-galactopyranoside (pNP-Gal) at 40 °C, higher than at 25 °C in the case of the conjugated enzyme. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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14 pages, 1481 KiB  
Article
Surface Segregation of Amphiphilic PDMS-Based Films Containing Terpolymers with Siloxane, Fluorinated and Ethoxylated Side Chains
by Elisa Martinelli, Elisa Guazzelli, Antonella Glisenti and Giancarlo Galli
Coatings 2019, 9(3), 153; https://doi.org/10.3390/coatings9030153 - 26 Feb 2019
Cited by 12 | Viewed by 3920
Abstract
(Meth)acrylic terpolymers carrying siloxane (Si), fluoroalkyl (F) and ethoxylated (EG) side chains were synthesized with comparable molar compositions and different lengths of the Si and EG side chains, while the length of the fluorinated side chain was kept constant. Such terpolymers were used [...] Read more.
(Meth)acrylic terpolymers carrying siloxane (Si), fluoroalkyl (F) and ethoxylated (EG) side chains were synthesized with comparable molar compositions and different lengths of the Si and EG side chains, while the length of the fluorinated side chain was kept constant. Such terpolymers were used as surface-active modifiers of polydimethylsiloxane (PDMS)-based films with a loading of 4 wt%. The surface chemical compositions of both the films and the pristine terpolymers were determined by angle-resolved X-ray photoelectron spectroscopy (AR-XPS) at different photoemission angles. The terpolymer was effectively segregated to the polymer−air interface of the films independent of the length of the constituent side chains. However, the specific details of the film surface modification depended upon the chemical structure of the terpolymer itself. The exceptionally high enrichment in F chains at the surface caused the accumulation of EG chains at the surface as well. The response of the films to the water environment was also proven to strictly depend on the type of terpolymer contained. While terpolymers with shorter EG chains appeared not to be affected by immersion in water for seven days, those containing longer EG chains underwent a massive surface reconstruction. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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13 pages, 3818 KiB  
Article
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 3685
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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10 pages, 3207 KiB  
Article
Characteristics of AISI 420 Stainless Steel Modified by Low-Temperature Plasma Carburizing with Gaseous Acetone
by Ruiliang Liu and Mufu Yan
Coatings 2019, 9(2), 75; https://doi.org/10.3390/coatings9020075 - 26 Jan 2019
Cited by 5 | Viewed by 4054
Abstract
In this research work, low-temperature carburizing of AISI 420 martensitic stainless steel was conducted at 460 °C for different amounts of time using an acetone source. The microstructure and phase structure of the carburized layers were characterized by optical microscope and X-ray diffraction. [...] Read more.
In this research work, low-temperature carburizing of AISI 420 martensitic stainless steel was conducted at 460 °C for different amounts of time using an acetone source. The microstructure and phase structure of the carburized layers were characterized by optical microscope and X-ray diffraction. The properties of the carburized layers were tested with a microhardness tester and an electrochemical workstation. The results indicate uniform layers are formed on martensitic stainless steel surfaces, and the carburized layers are mainly composed of carbon “expanded” α (αC) and Fe3C phases. The property tests indicated that after plasma–carburizing, the hardness of the stainless steel surface can reach up to 850 HV0.1. However, the corrosion resistance of stainless steel decreased slightly, and the corrosion characteristic of stainless steel was altered from pitting to general corrosion. The semiconductor characteristic of the passivation film on stainless steel was transformed from the p-type for untreated specimens to the n-type for carburized specimens. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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15 pages, 11489 KiB  
Article
Preparation and Corrosion Resistance of ETEO Modified Graphene Oxide/Epoxy Resin Coating
by Chunling Zhang, Xueyan Dai, Yingnan Wang, Guoen Sun, Peihong Li, Lijie Qu, Yanlong Sui and Yanli Dou
Coatings 2019, 9(1), 46; https://doi.org/10.3390/coatings9010046 - 15 Jan 2019
Cited by 28 | Viewed by 6074
Abstract
Improving the corrosion resistance of epoxy resin coatings has become the focus of current research. This study focuses on synthesizing a functionalized silane coupling agent (2-(3,4-epoxycyclohexyl)ethyl triethoxysilane) to modify the surface of graphene oxide to address nanomaterial agglomeration and enhance the coating resistance [...] Read more.
Improving the corrosion resistance of epoxy resin coatings has become the focus of current research. This study focuses on synthesizing a functionalized silane coupling agent (2-(3,4-epoxycyclohexyl)ethyl triethoxysilane) to modify the surface of graphene oxide to address nanomaterial agglomeration and enhance the coating resistance of the epoxy resin coating to corrosion by filling the coating with functionalized graphene oxide. Functionalized graphene oxide and coatings filled with functionalized graphene oxide were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The corrosion performance of each coating was studied by electrochemical impedance spectroscopy and a salt spray test. Results showed that the incorporation of functionalized graphene oxide enhances the corrosion protection performance of the epoxy composite coating, and the composite coating exhibited the best anticorrosion performance when the amount of functionalized graphene oxide was 0.7 wt %. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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14 pages, 6099 KiB  
Article
Cost-Effective Surface Modification of Carbon Cloth Electrodes for Microbial Fuel Cells by Candle Soot Coating
by Bor-Yann Chen, Yuan-Ting Tsao and Shih-Hang Chang
Coatings 2018, 8(12), 468; https://doi.org/10.3390/coatings8120468 - 17 Dec 2018
Cited by 16 | Viewed by 5524
Abstract
This study explored an economically-feasible and environmentally friendly attempt to provide more electrochemically promising carbon cloth anodes for microbial fuel cells (MFCs) by modifying them with candle soot coating. The sponge-like structure of the deposited candle soot apparently increased the surface areas of [...] Read more.
This study explored an economically-feasible and environmentally friendly attempt to provide more electrochemically promising carbon cloth anodes for microbial fuel cells (MFCs) by modifying them with candle soot coating. The sponge-like structure of the deposited candle soot apparently increased the surface areas of the carbon cloths for bacterial adhesion. The super-hydrophilicity of the deposited candle soot was more beneficial to bacterial propagation. The maximum power densities of MFCs configured with 20-s (13.6 ± 0.9 mW·m−2), 60-s (19.8 ± 0.2 mW·m−2), and 120-s (17.6 ± 0.8 mW·m−2) candle-soot-modified carbon cloth electrodes were apparently higher than that of an MFC configured with an unmodified electrode (10.2 ± 0.2 mW·m−2). The MFCs configured with the 20- and 120-s candle-soot-modified carbon cloth electrodes exhibited lower power densities than that of the MFC with the 60-s candle-soot-modified carbon cloth electrode. This suggested that the insufficient residence time of candle soot led to an incomplete formation of the hydrophilic surface, whereas protracted candle sooting would lead to a thick deposited soot film with a smaller conductivity. The application of candle soot for anode modification provided a simple, rapid, cost-effective, and environment-friendly approach to enhancing the electron-transfer capabilities of carbon cloth electrodes. However, a postponement in the MFC construction may lead to a deteriorated hydrophilicity of the candle-soot-modified carbon cloth. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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9 pages, 23269 KiB  
Article
Synthesis of Core-Shell MgO Alloy Nanoparticles for Steelmaking
by Jinglong Qu, Shufeng Yang, Hao Guo, Jingshe Li and Tiantian Wang
Coatings 2018, 8(5), 161; https://doi.org/10.3390/coatings8050161 - 27 Apr 2018
Cited by 3 | Viewed by 5415
Abstract
In this present study, we aimed to reduce the wetting angle of nanoparticles (NPs) in molten steel and thus, increase their utilization ratio in steel. In order to achieve this, a two-step process was used to synthesize a core-shell AlTi-MgO@C NP structure for [...] Read more.
In this present study, we aimed to reduce the wetting angle of nanoparticles (NPs) in molten steel and thus, increase their utilization ratio in steel. In order to achieve this, a two-step process was used to synthesize a core-shell AlTi-MgO@C NP structure for steelmaking through a dopamine polymerization process, which used an ammonium persulfate oxidant and high-temperature carbonization. The NP surface characterization was tested by scanning electron microscopy and field emission transmission electron microscopy, while the hydrodynamic NP size was measured by dynamic light scattering. The results showed that a carbon coating that had a thickness of 10 nm covered the NP surface, with the dispersion and stability of the particles in the aqueous solution having improved after the coating. The contact angle of the surface-treated NP was less than that of the uncoated NP in high-temperature molten steel and the corresponding wetting energy was smaller, which indicated improved wettability. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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9 pages, 1582 KiB  
Communication
Modulating the Partitioning of Microparticles in a Polyethylene Glycol (PEG)-Dextran (DEX) Aqueous Biphasic System by Surface Modification
by Chang Kyu Byun, Minkyung Kim and Daehee Kim
Coatings 2018, 8(3), 85; https://doi.org/10.3390/coatings8030085 - 26 Feb 2018
Cited by 11 | Viewed by 7710
Abstract
Aqueous two-phase systems (ATPSs) or aqueous biphasic systems are useful for biological separation/preparation and cell micropatterning. Specifically, aqueous two-phase systems (ATPSs) are not harmful to cells or biomaterials; therefore, they have been used to partition and isolate these materials from others. In this [...] Read more.
Aqueous two-phase systems (ATPSs) or aqueous biphasic systems are useful for biological separation/preparation and cell micropatterning. Specifically, aqueous two-phase systems (ATPSs) are not harmful to cells or biomaterials; therefore, they have been used to partition and isolate these materials from others. In this study, we suggest chemically modifying the surface of target materials (micro/nanoparticles, for example) with polymers, such as polyethylene glycol and dextran, which are the same polymer solutes as those in the ATPS. As a simple model, we chemically coated polyethylene glycol or dextran to the surface of polystyrene magnetic particles and observed selective partitioning of the surface modified particles to the phase in which the same polymer solutes are dominant. This approach follows the principle “like dissolves like” and can be expanded to other aqueous biphasic or multiphasic systems while consuming fewer chemicals than the conventional modulation of hydrophobicities of solute polymers to control partitioning in aqueous biphasic or multiphasic systems. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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2943 KiB  
Article
Fabrication of Microalloy Nitrided Layer on Low Carbon Steel by Nitriding Combined with Surface Nano-Alloying Pretreatment
by Jian Sun and Quantong Yao
Coatings 2016, 6(4), 63; https://doi.org/10.3390/coatings6040063 - 17 Nov 2016
Cited by 5 | Viewed by 6066
Abstract
Surface mechanical attrition treatment (SMAT) is an effective method to accelerate the nitriding process of metallic materials. In this work, a novel technique named surface nano-alloying (SNA) was developed on the basis of surface mechanical attrition treatment, which was employed as a pretreatment [...] Read more.
Surface mechanical attrition treatment (SMAT) is an effective method to accelerate the nitriding process of metallic materials. In this work, a novel technique named surface nano-alloying (SNA) was developed on the basis of surface mechanical attrition treatment, which was employed as a pretreatment for the nitriding of low carbon steel materials. The microstructure and surface properties of treated samples were investigated by SEM, XRD, TEM and the Vickers hardness test. Experimental results showed that a surface alloying layer (Cr element) of about 10–20 μm in thickness was formed on the low carbon steel sample after the surface nano-alloying treatment. After nitriding for the SNA sample, a complex compound layer composed of Fe2–3N, FeCr and Cr2N phases was fabricated. Moreover, the thickness of this compound layer was about 50 μm. Meanwhile, both the surface hardness and wear resistance of the SNA nitrided sample are better that those of the SMAT nitrided sample. This work offers a new approach for improving the nitriding process of steel materials. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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Review

Jump to: Research

21 pages, 781 KiB  
Review
Current Progress on the Surface Chemical Modification of Carbonaceous Materials
by Adeela Rehman, Mira Park and Soo-Jin Park
Coatings 2019, 9(2), 103; https://doi.org/10.3390/coatings9020103 - 8 Feb 2019
Cited by 98 | Viewed by 11908
Abstract
Carbon-based materials is considered one of the oldest and extensively studied research areas related to gas adsorption, energy storage and wastewater treatment for removing organic and inorganic contaminants. Efficient adsorption on activated carbon relies heavily upon the surface chemistry and textural features of [...] Read more.
Carbon-based materials is considered one of the oldest and extensively studied research areas related to gas adsorption, energy storage and wastewater treatment for removing organic and inorganic contaminants. Efficient adsorption on activated carbon relies heavily upon the surface chemistry and textural features of the main framework. The activation techniques and the nature of the precursor have strong impacts on surface functionalities. Consequently, the main emphasis for scientists is to innovate or improve the activation methods in an optimal way by selecting suitable precursors for desired adsorption. Various approaches, including acid treatment, base treatment and impregnation methods, have been used to design activated carbons with chemically modified surfaces. The present review article intends to deliver precise knowledge on efforts devoted by researchers to surface modification of activated carbons. Chemical modification approaches used to design modified activated carbons for gas adsorption, energy storage and water treatment are discussed here. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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3555 KiB  
Review
Recent Development in Phosphonic Acid-Based Organic Coatings on Aluminum
by Ruohan Zhao, Patrick Rupper and Sabyasachi Gaan
Coatings 2017, 7(9), 133; https://doi.org/10.3390/coatings7090133 - 23 Aug 2017
Cited by 59 | Viewed by 9813
Abstract
Research on corrosion protection of aluminum has intensified over the past decades due to environmental concerns regarding chromate-based conversion coatings and also the higher material performance requirements in automotive and aviation industries. Phosphonic acid-based organic and organic-inorganic coatings are increasingly investigated as potential [...] Read more.
Research on corrosion protection of aluminum has intensified over the past decades due to environmental concerns regarding chromate-based conversion coatings and also the higher material performance requirements in automotive and aviation industries. Phosphonic acid-based organic and organic-inorganic coatings are increasingly investigated as potential replacements of toxic and inefficient surface treatments for aluminum. In this review, we have briefly summarized recent work (since 2000) on pretreatments or coatings based on various phosphonic acids for aluminum and its alloys. Surface characterization methods, the mechanism of bonding of phosphonic acids to aluminum surface, methods for accessing the corrosion behavior of the treated aluminum, and applications have been discussed. There is a clear trend to develop multifunctional phosphonic acids and to produce hybrid organic-inorganic coatings. In most cases, the phosphonic acids are either assembled as a monolayer on the aluminum or incorporated in a coating matrix on top of aluminum, which is either organic or organic-inorganic in nature. Increased corrosion protection has often been observed. However, much work is still needed in terms of their ecological impact and adaptation to the industrially-feasible process for possible commercial exploitation. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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7173 KiB  
Review
Progress in Wear Resistant Materials for Total Hip Arthroplasty
by Rohit Khanna, Joo L. Ong, Ebru Oral and Roger J. Narayan
Coatings 2017, 7(7), 99; https://doi.org/10.3390/coatings7070099 - 9 Jul 2017
Cited by 27 | Viewed by 10891
Abstract
Current trends in total hip arthroplasty (THA) are to develop novel artificial hip joints with high wear resistance and mechanical reliability with a potential to last for at least 25–30 years for both young and old active patients. Currently used artificial hip joints [...] Read more.
Current trends in total hip arthroplasty (THA) are to develop novel artificial hip joints with high wear resistance and mechanical reliability with a potential to last for at least 25–30 years for both young and old active patients. Currently used artificial hip joints are mainly composed of femoral head of monolithic alumina or alumina-zirconia composites articulating against cross-linked polyethylene liner of acetabular cup or Co-Cr alloy in a self-mated configuration. However, the possibility of fracture of ceramics or its composites, PE wear debris-induced osteolysis, and hypersensitivity issue due to metal ion release cannot be eliminated. In some cases, thin ultra-hard diamond-based, TiN coatings on Ti-6A-4V or thin zirconia layer on the Zr-Nb alloy have been fabricated to develop high wear resistant bearing surfaces. However, these coatings showed poor adhesion in tribological testing. To provide high wear resistance and mechanical reliability to femoral head, a new kind of ceramic/metal artificial hip joint hybrid was recently proposed in which 10–15 μm thick dense layer of pure α-alumina was formed onto Ti-6Al-4V alloy by deposition of Al metal layer by cold spraying or cold metal transfer methods with 1–2 μm thick Al3Ti reaction layer formed at their interface to improve adhesion. An optimal micro-arc oxidation treatment transformed Al to dense α-alumina layer, which showed high Vickers hardness 1900 HV and good adhesion to the substrate. Further tribological and cytotoxicity analyses of these hybrids will determine their efficacy for potential use in THA. Full article
(This article belongs to the Special Issue Surface Chemical Modification)
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