Plasma electrolytic oxidation is a well-known technique for surface modification of biomedical magnesium alloys,with good corrosion protection and the ability to produce biocompatible and bioactive coatings.In this st...Plasma electrolytic oxidation is a well-known technique for surface modification of biomedical magnesium alloys,with good corrosion protection and the ability to produce biocompatible and bioactive coatings.In this study,calcium-phosphate coatings were produced on WE43 magnesium alloy for use,as orthopedic implants.Coating formation was prepared using different oxidation parameters with various duty ratios(DR)of 15,25 and 50%and current ratios(R)-2 or 1.6.Application of R with excess cathodic current(R>1)in processes with DR≥25%allowed attaining the soft-sparking regime(SSR)that resulted in thicker oxide coatings with higher degree of crystallinity compared to the films obtained without SSR.The results of the corrosion tests contributed to a noticeable improvement in the corrosion resistance of the magnesium alloy.Optimization of the oxidation parameters allowed the selection of the variants with the most favorable degradation behavior over the tested immersion period,indicating a successful modification of the magnesium alloy surface to obtain an implant biomaterial capable of providing controlled degradation.Furthermore,biological evaluation of the produced coatings showed that the proposed surface modifications significantly reduced the cytotoxic effects observed in direct contact with the material while still maintaining the cell proliferation-promoting effects of the material eluents.展开更多
Electrospinning has gained significant importance across various fields,including biomedicine,filtration,and packaging due to the control it provides over the properties of the resulting materials,such as fiber diamet...Electrospinning has gained significant importance across various fields,including biomedicine,filtration,and packaging due to the control it provides over the properties of the resulting materials,such as fiber diameter and membrane thickness.Chitosan is a biopolymer that can be utilized with both natural and synthetic copolymers,owing to its therapeutic potential,biocompatibility,and biodegradability.However,producing electrospun chitosan is challenging due to its high solution viscosity,which often results in the formation of beads instead of uniform fibers.To address this issue,the spinnability of chitosan is significantly enhanced,and the production of continuous nanofibers is facilitated by combining it with polymers such as polyethylene oxide(PEO)in suitable ratios.These chitosan–PEO nanofibers are primarily used in biomedical applications,including wound healing,drug delivery systems,and tissue engineering scaffolds.Additionally,they have shown promise in water treatment,filtration membranes,and packaging.Among all the nanofiber mats,chitosan/PEO-AC had the smallest fiber diameter(83±12.5 nm),chitosan/PEO_45S5 had the highest tensile strength(1611±678 MPa).This comprehensive review highlights recent advancements,ongoing challenges,and future directions in the electrospinning of chitosan-based fibers assisted by PEO.展开更多
The vip-host chemistry in polymer electrolytes plays a crucial role for all-solid-state Li metal batteries,where the stable operation of such batteries heavily relies on high ion conductivity,strong mechanical prope...The vip-host chemistry in polymer electrolytes plays a crucial role for all-solid-state Li metal batteries,where the stable operation of such batteries heavily relies on high ion conductivity,strong mechanical properties,and stable interfaces of the electrolyte.While traditional ceramic fillers can boost ion conductivity,they fail to improve interfacial stability.In this study,we introduce intermolecular hydrogen bonding into a polyethylene oxide(PEO)-based polymer electrolyte through the incorporation of metal organic framework(MOF)and lithium nitrate additives.The hydrogen on the PEO chain is found to be tightly interacted with the oxygen nodes of UiO-66 MOF and nitrate anions,creating a cross-linked framework that reduces the crystallinity of the PEO and enhances the integrity of composite.This interaction induces a beneficial Li3N and LiF-rich solid electrolyte interphase,ensuring 2000 h of stable lithium metal operation without short-circuits.The strong polysulfide adsorption enables compatibility with high-capacity sulfur cathodes,resulting in solidstate Li-S batteries that can achieve a high capacity of 913.8 mAh·g^(-1)and exhibit stable cycling performance.This work demonstrates the deep understanding of vip-host chemistry in polymer electrolytes and their potential in developing energy-dense solid-state Li metal batteries.展开更多
The plasma electrolytic oxidation(PEO)procedure is utilized in order to amend the surface properties of Mg and its alloys.This procedure creates a ceramic coating on the surface applying high-voltage.The presence of d...The plasma electrolytic oxidation(PEO)procedure is utilized in order to amend the surface properties of Mg and its alloys.This procedure creates a ceramic coating on the surface applying high-voltage.The presence of deep pores and porosities in the surface that affect the corrosion resistance of the coatings is one of the PEO procedure limitations.One of the useful methods to decrease porosities of coating and improve its final properties is changing electrolyte conditions based on the presence of micro-and nanoparticles.The present paper reviews the mechanisms of particle adsorption and composition in PEO thin films in addition to the effect of particle addition on the microstructure,composition and corrosion behavior of coatings that were applied on magnesium alloys.展开更多
As an efficient surface modification approach,the plasma electrolytic oxidation(PEO)technique can boost the capability of wear protection in Mg and its alloys by applying a hard and thick ceramic coating.In this proce...As an efficient surface modification approach,the plasma electrolytic oxidation(PEO)technique can boost the capability of wear protection in Mg and its alloys by applying a hard and thick ceramic coating.In this procedure,more efficient protection can be acquired via adding additives(in the form of particle,powder,sheet,etc.)into solutions and producing composite coatings.These additives result in more efficient protection against wear via getting stuck in the cracks and pores of coatings and rising the thickness,hardness,and diminishing the porosity size and content.The efficiency of each additive can be changed owing to its intrinsic properties like melting point,size,participation type(reactive,partly reactive,or inert)and potential of zeta.In this review,the effects of distinct additives in nano-and micro-scale size on wear behavior of PEO coatings on Mg and its alloys is going to be reviewed.展开更多
Magnesium has been known as an appropriate biological material on account of its good biocompatibility and biodegradability properties in addition to advantageous mechanical properties.Mg and its alloys are of poor co...Magnesium has been known as an appropriate biological material on account of its good biocompatibility and biodegradability properties in addition to advantageous mechanical properties.Mg and its alloys are of poor corrosion resistance.Its high corrosion rate leads to its quick decomposition in the corrosive ambiance and as a result weakening its mechanical properties and before it is repaired,it will vanish.The corrosion and degradation rate must be controlled in the body to advance the usage of Mg and its alloys as implants.Different techniques have been utilized to boost biological properties.Plasma electrolytic oxidation(PEO)can provide porous and biocompatible coatings for implants among various techniques.Biodegradable implants are generally supposed to show enough corrosion resistance and mechanical integrity in the body environment.Much research has been carried out in order to produce PEO coatings containing calcium phosphate compounds.Calcium phosphates are really similar to bone mineral composition and present great biocompatibility.The present study deals with the usage of calcium phosphates as biocompatible coatings applied on Mg and its alloys to study the properties and control the corrosion rate.展开更多
Magnesium(Mg)and its alloys have received much attention in a lot of areas due to their special chemical and physical properties.Nevertheless,high corrosion rates are a limiting factor.The plasma electrolytic oxidatio...Magnesium(Mg)and its alloys have received much attention in a lot of areas due to their special chemical and physical properties.Nevertheless,high corrosion rates are a limiting factor.The plasma electrolytic oxidation(PEO)technique is a simple approach to place an oxide film on the surface of light metals like Mg alloys.This method has been considered for controlling the rate of corrosion and improving some other properties.On the other hand,PEO coatings cannot make enough protection of Magnesium alloys for a long time due to porosity and fine cracks.Therefore,PEO-based composite coatings are used to make adequate corrosion protection on the Mg alloys surface.The popularity of these coatings is due to their good corrosion resistance,simplicity,high coating capability,and cost-effectiveness in complex segments.Formation of an organic layer on the surface of PEO coating is one of the effective methods to close the defects and thus prevent the corrosive species penetration into the substrate.Coating the PEO coating with a polymer layer can be a good solution to control the amount of damage and improve the corrosion and abrasion resistance.In addition,PEO coating can eliminate the problems of insufficient adhesion of polymer coatings and is considered as a suitable base for composite coatings.This review paper presents the corrosion and abrasion behavior of the PEO/Polymer dual coating system on Mg alloys.Given the fundamental role of coatings thickness and morphology in wear and corrosion behavior,these aspects have been highly discussed in this study.展开更多
In the polyoxyethylene(PEO)-based solid-state electrolytes,the low ionic conductivity of lithium ions limits its application in solid-state lithium batteries,so optimizing the conduction path of lithium ions is benefi...In the polyoxyethylene(PEO)-based solid-state electrolytes,the low ionic conductivity of lithium ions limits its application in solid-state lithium batteries,so optimizing the conduction path of lithium ions is beneficial to improve the ionic conductivity.In this work,we report the use of hydrothermal carbon nano-sphere(HCS)modified glass fibers(GF)as a functional filler(GF@HCS)to improve the ionic conductivity of PEO composite solidstate electrolytes.The oxygen atoms in the hydroxyl groups on the surface of HCS can be complexed with Li ions as its transport sites,which means that it can promote the longdistance transport of Li ions along the glass fiber surface.With addition of 2 wt%GF@HCS fillers,the degree of crystallinity of PEO composite solid-state electrolyte is the smallest,and the ionic conductivity is significantly increased from 8.9×10^(-5) to 4.4×10^(-4) S·cm^(-1) at 60℃.Moreover,the PEO composite solid-state electrolyte exhibits better lithium-metal interface stability in symmetric lithium batteries and superior rate performance in LiFePO4 solid-state batteries.展开更多
AZ91 Mg alloy was treated through a new localized PEO(Plasma Electrolytic Oxidation)coating approach,using electrolyte solutions with varying ZrO2 nanoparticles concentration(2-8 g/L)and processing times.With increase...AZ91 Mg alloy was treated through a new localized PEO(Plasma Electrolytic Oxidation)coating approach,using electrolyte solutions with varying ZrO2 nanoparticles concentration(2-8 g/L)and processing times.With increase in the ZrO2 concentration,several microstructural changes were observed including;formation of cluster-type structure,damage to the inner layers(∼30 min)and sealing of defects.Corrosion analysis of the final coatings was carried out using potentiodynamic polarization,electrochemical impedance spectroscopy and post-corrosion analysis.It was explored that highest corrosion resistance(Rp∼81.17 kΩcm^2)of the coatings was obtained for ZrO2∼2 g/L.However,higher concentration of the ZrO2 nanoparticles caused weak crystalline coating structure,due to unstable and lower intensity discharges,thus failed to offer high corrosion resistance performance.展开更多
Unlike other parts of the body, jaw defection often involves dental and periodontal tissues, which colonized a great many oral anaerobic bacteria. As a remarkable degradable material, magnesium has become an excellent...Unlike other parts of the body, jaw defection often involves dental and periodontal tissues, which colonized a great many oral anaerobic bacteria. As a remarkable degradable material, magnesium has become an excellent candidate for orthopedic appliances recently. But the high degradation rate is still a big problem. Making a biodegradable coating with good biocompatibility to slow down the degeneration rate of magnesium is one of the best methods. However, protective coatings will impair the antibacterial effects of magnesium which is caused by the rise of p H value throughout its degradation. To solve this problem, a series of composite coatings with different amounts of Cu O particles(3, 5 and 7 wt.%) were fabricated on pure magnesium through plasma electrolytic oxidation(PEO) to investigate in vitro biocompatibility and the antibacterial abilities against Porphyromonas gingivalis(P. gingivalis). Surface characterization and degradation behavior of the copper-bearing PEO coatings were also systematically studied. Furthermore,the most optimum coating was also systematically studied by X-ray photoelectron spectroscopy(XPS)and electrochemical corrosion test. Results of the present research revealed that adding proper amount of Cu O into PEO coatings could greatly improve the antibacterial abilities of the PEO coatings. The antibacterial activities of copper-bearing PEO coatings were excellent and revealed concentration-dependent and time-dependent. Biocompatibility of copper-bearing PEO coatings showed that proper amount of Cu could promote cell proliferation. Compared with other PEO coatings in this study, PEO-7 Cu showed some inhibition effects on cell proliferation and adhesion for long-term use. Electrochemical corrosion tests and immersion tests showed that PEO-5 Cu and PEO-7 Cu copper-bearing PEO coatings would provide satisfying corrosion resistance effects, while PEO-3 Cu was poorer than PEO coatings without Cu. However, compared with uncoated pure magnesium, the corrosion resistance of the PEO coating was much better. Based on the results of antibacterial ability, biocompatibility, and corrosion resistance of the above copper-bearing PEO coatings, PEO-5 Cu in this research was recommended to be used in patients with jaw defects.展开更多
The unsatisfactory corrosion properties of Mg-based alloys pose a significant obstacle to their widespread application. Plasma electrolytic oxidation(PEO) is a prevalent and effective coating method that produces a ce...The unsatisfactory corrosion properties of Mg-based alloys pose a significant obstacle to their widespread application. Plasma electrolytic oxidation(PEO) is a prevalent and effective coating method that produces a ceramic-like oxide coating on the surface of Mg-based alloys,enhancing their resistance to corrosion. Research has demonstrated that PEO treatment can substantially improve the corrosion performance of alloys based on magnesium in the short term. In an effort to enhance the corrosion resistance of PEO coatings over an extended period of time, researchers have turned their attention to the use of laser processes as both pre-and post-treatments in conjunction with the PEO process. Various laser processes, such as laser shock melting(LSM), laser shock adhesion(LSA), laser shock texturing(LST), and laser shock peening(LSP), have been investigated for their potential to improve PEO coatings on Mg substrates and their alloys. These laser melting processes can homogenize and alter the microstructure of Mg-based alloys while leaving the bulk material unchanged, thereby modifying the substrate surface. However, the porous and rough structure of PEO coatings, with their open and interconnected pore structure, can reduce their long-term corrosion resistance. As such, various laser processes are well-suited for surface modification of these coatings. This study will first examine the PEO process and the various types of laser processes used in this process, before investigating the corrosion behavior of PEO coatings in conjunction with laser pre-and post-treatment processes.展开更多
Recently,developing bioactive and biocompatible materials based on Mg and Mg-alloys for implant applications has drawn attention among researchers owing to their suitable body degradability.Implementing Mg and its all...Recently,developing bioactive and biocompatible materials based on Mg and Mg-alloys for implant applications has drawn attention among researchers owing to their suitable body degradability.Implementing Mg and its alloys reduces the risk of long-term incompatibility with tissues because of their close mechanical properties and no need for re-operation to remove the implant.Nevertheless,the degradation rate of the implant needs to be controlled because production of hydrogen gas and accumulation of its bubbles increases local pH around the implants.To confine the integrity of implants and the body,the corrosion concern in the body fluid requires to be addressed.Surface modification as one of the effective strategies can improve corrosion resistance.Besides,it creates a suitable surface for bone grafting and cell growth.The development of proper surface-coated implants needs appropriate techniques and approaches.Plasma electrolytic oxidation(PEO)coating can provide long-term protection by providing a ceramic layer and improving the implant’s biocompatibility.Herein,a general review of in-vivo and in-vitro evaluation of PEO coatings on Mg and Mg-alloys has been carried out.Recent advances in surface modification on Mg and Mg-alloys have been discussed,however,the need for reliable laboratory models to predict in-vivo degradation is still valid.展开更多
Magnesium(Mg)alloys are lightweight materials with excellent mechanical properties,making them attractive for various applications,including aerospace,automotive,and biomedical industries.However,the practical applica...Magnesium(Mg)alloys are lightweight materials with excellent mechanical properties,making them attractive for various applications,including aerospace,automotive,and biomedical industries.However,the practical application of Mg alloys is limited due to their high susceptibility to corrosion.Plasma electrolytic oxidation(PEO),or micro-arc oxidation(MAO),is a coating method that boosts Mg alloys'corrosion resistance.However,despite the benefits of PEO coatings,they can still exhibit certain limitations,such as failing to maintain long-term protection as a result of their inherent porosity.To address these challenges,researchers have suggested the use of inhibitors in combination with PEO coatings on Mg alloys.Inhibitors are chemical compounds that can be incorporated into the coating or applied as a post-treatment to further boost the corrosion resistance of the PEO-coated Mg alloys.Corrosion inhibitors,whether organic or inorganic,can act by forming a protective barrier,hindering the corrosion process,or modifying the surface properties to reduce susceptibility to corrosion.Containers can be made of various materials,including polyelectrolyte shells,layered double hydroxides,polymer shells,and mesoporous inorganic materials.Encapsulating corrosion inhibitors in containers fully compatible with the coating matrix and substrate is a promising approach for their incorporation.Laboratory studies of the combination of inhibitors with PEO coatings on Mg alloys have shown promising results,demonstrating significant corrosion mitigation,extending the service life of Mg alloy components in aggressive environments,and providing self-healing properties.In general,this review presents available information on the incorporation of inhibitors with PEO coatings,which can lead to improved performance of Mg alloy components in demanding environments.展开更多
基金funded by Silesian University of Technology,no.07/020/BKM24/0104.
文摘Plasma electrolytic oxidation is a well-known technique for surface modification of biomedical magnesium alloys,with good corrosion protection and the ability to produce biocompatible and bioactive coatings.In this study,calcium-phosphate coatings were produced on WE43 magnesium alloy for use,as orthopedic implants.Coating formation was prepared using different oxidation parameters with various duty ratios(DR)of 15,25 and 50%and current ratios(R)-2 or 1.6.Application of R with excess cathodic current(R>1)in processes with DR≥25%allowed attaining the soft-sparking regime(SSR)that resulted in thicker oxide coatings with higher degree of crystallinity compared to the films obtained without SSR.The results of the corrosion tests contributed to a noticeable improvement in the corrosion resistance of the magnesium alloy.Optimization of the oxidation parameters allowed the selection of the variants with the most favorable degradation behavior over the tested immersion period,indicating a successful modification of the magnesium alloy surface to obtain an implant biomaterial capable of providing controlled degradation.Furthermore,biological evaluation of the produced coatings showed that the proposed surface modifications significantly reduced the cytotoxic effects observed in direct contact with the material while still maintaining the cell proliferation-promoting effects of the material eluents.
文摘Electrospinning has gained significant importance across various fields,including biomedicine,filtration,and packaging due to the control it provides over the properties of the resulting materials,such as fiber diameter and membrane thickness.Chitosan is a biopolymer that can be utilized with both natural and synthetic copolymers,owing to its therapeutic potential,biocompatibility,and biodegradability.However,producing electrospun chitosan is challenging due to its high solution viscosity,which often results in the formation of beads instead of uniform fibers.To address this issue,the spinnability of chitosan is significantly enhanced,and the production of continuous nanofibers is facilitated by combining it with polymers such as polyethylene oxide(PEO)in suitable ratios.These chitosan–PEO nanofibers are primarily used in biomedical applications,including wound healing,drug delivery systems,and tissue engineering scaffolds.Additionally,they have shown promise in water treatment,filtration membranes,and packaging.Among all the nanofiber mats,chitosan/PEO-AC had the smallest fiber diameter(83±12.5 nm),chitosan/PEO_45S5 had the highest tensile strength(1611±678 MPa).This comprehensive review highlights recent advancements,ongoing challenges,and future directions in the electrospinning of chitosan-based fibers assisted by PEO.
基金financially supported by the National Natural Science Foundation of China(Nos.22272080(M.Y.)and 52272218(H.X.))the Fundamental Research Funds for the Central Universities(No.2242024k30047).
文摘The vip-host chemistry in polymer electrolytes plays a crucial role for all-solid-state Li metal batteries,where the stable operation of such batteries heavily relies on high ion conductivity,strong mechanical properties,and stable interfaces of the electrolyte.While traditional ceramic fillers can boost ion conductivity,they fail to improve interfacial stability.In this study,we introduce intermolecular hydrogen bonding into a polyethylene oxide(PEO)-based polymer electrolyte through the incorporation of metal organic framework(MOF)and lithium nitrate additives.The hydrogen on the PEO chain is found to be tightly interacted with the oxygen nodes of UiO-66 MOF and nitrate anions,creating a cross-linked framework that reduces the crystallinity of the PEO and enhances the integrity of composite.This interaction induces a beneficial Li3N and LiF-rich solid electrolyte interphase,ensuring 2000 h of stable lithium metal operation without short-circuits.The strong polysulfide adsorption enables compatibility with high-capacity sulfur cathodes,resulting in solidstate Li-S batteries that can achieve a high capacity of 913.8 mAh·g^(-1)and exhibit stable cycling performance.This work demonstrates the deep understanding of vip-host chemistry in polymer electrolytes and their potential in developing energy-dense solid-state Li metal batteries.
文摘The plasma electrolytic oxidation(PEO)procedure is utilized in order to amend the surface properties of Mg and its alloys.This procedure creates a ceramic coating on the surface applying high-voltage.The presence of deep pores and porosities in the surface that affect the corrosion resistance of the coatings is one of the PEO procedure limitations.One of the useful methods to decrease porosities of coating and improve its final properties is changing electrolyte conditions based on the presence of micro-and nanoparticles.The present paper reviews the mechanisms of particle adsorption and composition in PEO thin films in addition to the effect of particle addition on the microstructure,composition and corrosion behavior of coatings that were applied on magnesium alloys.
文摘As an efficient surface modification approach,the plasma electrolytic oxidation(PEO)technique can boost the capability of wear protection in Mg and its alloys by applying a hard and thick ceramic coating.In this procedure,more efficient protection can be acquired via adding additives(in the form of particle,powder,sheet,etc.)into solutions and producing composite coatings.These additives result in more efficient protection against wear via getting stuck in the cracks and pores of coatings and rising the thickness,hardness,and diminishing the porosity size and content.The efficiency of each additive can be changed owing to its intrinsic properties like melting point,size,participation type(reactive,partly reactive,or inert)and potential of zeta.In this review,the effects of distinct additives in nano-and micro-scale size on wear behavior of PEO coatings on Mg and its alloys is going to be reviewed.
文摘Magnesium has been known as an appropriate biological material on account of its good biocompatibility and biodegradability properties in addition to advantageous mechanical properties.Mg and its alloys are of poor corrosion resistance.Its high corrosion rate leads to its quick decomposition in the corrosive ambiance and as a result weakening its mechanical properties and before it is repaired,it will vanish.The corrosion and degradation rate must be controlled in the body to advance the usage of Mg and its alloys as implants.Different techniques have been utilized to boost biological properties.Plasma electrolytic oxidation(PEO)can provide porous and biocompatible coatings for implants among various techniques.Biodegradable implants are generally supposed to show enough corrosion resistance and mechanical integrity in the body environment.Much research has been carried out in order to produce PEO coatings containing calcium phosphate compounds.Calcium phosphates are really similar to bone mineral composition and present great biocompatibility.The present study deals with the usage of calcium phosphates as biocompatible coatings applied on Mg and its alloys to study the properties and control the corrosion rate.
文摘Magnesium(Mg)and its alloys have received much attention in a lot of areas due to their special chemical and physical properties.Nevertheless,high corrosion rates are a limiting factor.The plasma electrolytic oxidation(PEO)technique is a simple approach to place an oxide film on the surface of light metals like Mg alloys.This method has been considered for controlling the rate of corrosion and improving some other properties.On the other hand,PEO coatings cannot make enough protection of Magnesium alloys for a long time due to porosity and fine cracks.Therefore,PEO-based composite coatings are used to make adequate corrosion protection on the Mg alloys surface.The popularity of these coatings is due to their good corrosion resistance,simplicity,high coating capability,and cost-effectiveness in complex segments.Formation of an organic layer on the surface of PEO coating is one of the effective methods to close the defects and thus prevent the corrosive species penetration into the substrate.Coating the PEO coating with a polymer layer can be a good solution to control the amount of damage and improve the corrosion and abrasion resistance.In addition,PEO coating can eliminate the problems of insufficient adhesion of polymer coatings and is considered as a suitable base for composite coatings.This review paper presents the corrosion and abrasion behavior of the PEO/Polymer dual coating system on Mg alloys.Given the fundamental role of coatings thickness and morphology in wear and corrosion behavior,these aspects have been highly discussed in this study.
基金financially supported by the National Natural Science Foundation of China(Nos.21875195,22021001 and 52172184)。
文摘In the polyoxyethylene(PEO)-based solid-state electrolytes,the low ionic conductivity of lithium ions limits its application in solid-state lithium batteries,so optimizing the conduction path of lithium ions is beneficial to improve the ionic conductivity.In this work,we report the use of hydrothermal carbon nano-sphere(HCS)modified glass fibers(GF)as a functional filler(GF@HCS)to improve the ionic conductivity of PEO composite solidstate electrolytes.The oxygen atoms in the hydroxyl groups on the surface of HCS can be complexed with Li ions as its transport sites,which means that it can promote the longdistance transport of Li ions along the glass fiber surface.With addition of 2 wt%GF@HCS fillers,the degree of crystallinity of PEO composite solid-state electrolyte is the smallest,and the ionic conductivity is significantly increased from 8.9×10^(-5) to 4.4×10^(-4) S·cm^(-1) at 60℃.Moreover,the PEO composite solid-state electrolyte exhibits better lithium-metal interface stability in symmetric lithium batteries and superior rate performance in LiFePO4 solid-state batteries.
基金The current study was supported by“The Hongik University New Faculty Research Support Fund”Hongik University.
文摘AZ91 Mg alloy was treated through a new localized PEO(Plasma Electrolytic Oxidation)coating approach,using electrolyte solutions with varying ZrO2 nanoparticles concentration(2-8 g/L)and processing times.With increase in the ZrO2 concentration,several microstructural changes were observed including;formation of cluster-type structure,damage to the inner layers(∼30 min)and sealing of defects.Corrosion analysis of the final coatings was carried out using potentiodynamic polarization,electrochemical impedance spectroscopy and post-corrosion analysis.It was explored that highest corrosion resistance(Rp∼81.17 kΩcm^2)of the coatings was obtained for ZrO2∼2 g/L.However,higher concentration of the ZrO2 nanoparticles caused weak crystalline coating structure,due to unstable and lower intensity discharges,thus failed to offer high corrosion resistance performance.
基金financially supported by the National Natural Science Foundation of China(No.U1737102)the Shenyang Key R&D and Technology Transfer Program(No.Z18-0-027)+1 种基金the Shenyang Science and Technology Program(No.19-112-4-029)the Fundamental Research Funds for the Central Universities(N181903009and N2002009)。
文摘Unlike other parts of the body, jaw defection often involves dental and periodontal tissues, which colonized a great many oral anaerobic bacteria. As a remarkable degradable material, magnesium has become an excellent candidate for orthopedic appliances recently. But the high degradation rate is still a big problem. Making a biodegradable coating with good biocompatibility to slow down the degeneration rate of magnesium is one of the best methods. However, protective coatings will impair the antibacterial effects of magnesium which is caused by the rise of p H value throughout its degradation. To solve this problem, a series of composite coatings with different amounts of Cu O particles(3, 5 and 7 wt.%) were fabricated on pure magnesium through plasma electrolytic oxidation(PEO) to investigate in vitro biocompatibility and the antibacterial abilities against Porphyromonas gingivalis(P. gingivalis). Surface characterization and degradation behavior of the copper-bearing PEO coatings were also systematically studied. Furthermore,the most optimum coating was also systematically studied by X-ray photoelectron spectroscopy(XPS)and electrochemical corrosion test. Results of the present research revealed that adding proper amount of Cu O into PEO coatings could greatly improve the antibacterial abilities of the PEO coatings. The antibacterial activities of copper-bearing PEO coatings were excellent and revealed concentration-dependent and time-dependent. Biocompatibility of copper-bearing PEO coatings showed that proper amount of Cu could promote cell proliferation. Compared with other PEO coatings in this study, PEO-7 Cu showed some inhibition effects on cell proliferation and adhesion for long-term use. Electrochemical corrosion tests and immersion tests showed that PEO-5 Cu and PEO-7 Cu copper-bearing PEO coatings would provide satisfying corrosion resistance effects, while PEO-3 Cu was poorer than PEO coatings without Cu. However, compared with uncoated pure magnesium, the corrosion resistance of the PEO coating was much better. Based on the results of antibacterial ability, biocompatibility, and corrosion resistance of the above copper-bearing PEO coatings, PEO-5 Cu in this research was recommended to be used in patients with jaw defects.
文摘The unsatisfactory corrosion properties of Mg-based alloys pose a significant obstacle to their widespread application. Plasma electrolytic oxidation(PEO) is a prevalent and effective coating method that produces a ceramic-like oxide coating on the surface of Mg-based alloys,enhancing their resistance to corrosion. Research has demonstrated that PEO treatment can substantially improve the corrosion performance of alloys based on magnesium in the short term. In an effort to enhance the corrosion resistance of PEO coatings over an extended period of time, researchers have turned their attention to the use of laser processes as both pre-and post-treatments in conjunction with the PEO process. Various laser processes, such as laser shock melting(LSM), laser shock adhesion(LSA), laser shock texturing(LST), and laser shock peening(LSP), have been investigated for their potential to improve PEO coatings on Mg substrates and their alloys. These laser melting processes can homogenize and alter the microstructure of Mg-based alloys while leaving the bulk material unchanged, thereby modifying the substrate surface. However, the porous and rough structure of PEO coatings, with their open and interconnected pore structure, can reduce their long-term corrosion resistance. As such, various laser processes are well-suited for surface modification of these coatings. This study will first examine the PEO process and the various types of laser processes used in this process, before investigating the corrosion behavior of PEO coatings in conjunction with laser pre-and post-treatment processes.
文摘Recently,developing bioactive and biocompatible materials based on Mg and Mg-alloys for implant applications has drawn attention among researchers owing to their suitable body degradability.Implementing Mg and its alloys reduces the risk of long-term incompatibility with tissues because of their close mechanical properties and no need for re-operation to remove the implant.Nevertheless,the degradation rate of the implant needs to be controlled because production of hydrogen gas and accumulation of its bubbles increases local pH around the implants.To confine the integrity of implants and the body,the corrosion concern in the body fluid requires to be addressed.Surface modification as one of the effective strategies can improve corrosion resistance.Besides,it creates a suitable surface for bone grafting and cell growth.The development of proper surface-coated implants needs appropriate techniques and approaches.Plasma electrolytic oxidation(PEO)coating can provide long-term protection by providing a ceramic layer and improving the implant’s biocompatibility.Herein,a general review of in-vivo and in-vitro evaluation of PEO coatings on Mg and Mg-alloys has been carried out.Recent advances in surface modification on Mg and Mg-alloys have been discussed,however,the need for reliable laboratory models to predict in-vivo degradation is still valid.
文摘Magnesium(Mg)alloys are lightweight materials with excellent mechanical properties,making them attractive for various applications,including aerospace,automotive,and biomedical industries.However,the practical application of Mg alloys is limited due to their high susceptibility to corrosion.Plasma electrolytic oxidation(PEO),or micro-arc oxidation(MAO),is a coating method that boosts Mg alloys'corrosion resistance.However,despite the benefits of PEO coatings,they can still exhibit certain limitations,such as failing to maintain long-term protection as a result of their inherent porosity.To address these challenges,researchers have suggested the use of inhibitors in combination with PEO coatings on Mg alloys.Inhibitors are chemical compounds that can be incorporated into the coating or applied as a post-treatment to further boost the corrosion resistance of the PEO-coated Mg alloys.Corrosion inhibitors,whether organic or inorganic,can act by forming a protective barrier,hindering the corrosion process,or modifying the surface properties to reduce susceptibility to corrosion.Containers can be made of various materials,including polyelectrolyte shells,layered double hydroxides,polymer shells,and mesoporous inorganic materials.Encapsulating corrosion inhibitors in containers fully compatible with the coating matrix and substrate is a promising approach for their incorporation.Laboratory studies of the combination of inhibitors with PEO coatings on Mg alloys have shown promising results,demonstrating significant corrosion mitigation,extending the service life of Mg alloy components in aggressive environments,and providing self-healing properties.In general,this review presents available information on the incorporation of inhibitors with PEO coatings,which can lead to improved performance of Mg alloy components in demanding environments.
