High energy density and low-cost lithium-sulfur batteries have been considered as one of the most promising candidates for next-generation energy storage systems.However,the intrinsic problems of the sulfur cathode se...High energy density and low-cost lithium-sulfur batteries have been considered as one of the most promising candidates for next-generation energy storage systems.However,the intrinsic problems of the sulfur cathode severely restrict their further practical application.Here,a unique double-shell architecture composed of hollow carbon spheres@interlayer-expanded and sulfur-enriched MoS2+x nanocoating composite has been developed as an efficient sulfur host.A uniform precursor coating derived from heteropolyanions-induced polymerization of pyrrole leads to space confinement effect during the in-situ sulfurization process,which generates the interlayer-expanded and sulfur-enriched MoS2+x nanosheets on amorphous carbon hollow spheres.This new sulfur host possesses multifarious merits including sufficient voids for loading sulfur active materials,high electronic conductivity,and fast lithium-ion diffusive pathways.In addition,additional active edge sites of MoS2+x accompanied by the nitrogen-doped carbon species endow the sulfur host with immobilizing and catalyzing effects on the soluble polysulfide species,dramatically accelerating their conversion kinetics and re-utilization.The detailed defect-induced interface catalytic reaction mechanism is firstly proposed.As expected,the delicately-designed sulfur host exhibits an outstanding initial discharge capacity of 1,249 mAh·g^−1 at 0.2 C and a desirable rate performance(593 mAh·g^−1 at 5.0 C),implying its great prospects in achieving superior electrochemical performances for advanced lithium sulfur batteries.展开更多
Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of rec...Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of receiving surface waters. Formation of unwanted disinfection by-products(DBPs) resulting from conventional disinfection technologies reveals the need for the development of new sustainable alternatives. Quaternary Ammonium Compounds(QACs) are cationic surfactants widely known for their effective biocidal properties at the ppm level. In this study, a novel silica-based antimicrobial nanofilm was developed using a composite of silica-modified QAC(Fixed-Quat) and applied to a fiberglass mesh as an active surface via sol–gel technique. The synthesized Fixed-Quat nanocoating was found to be effective against E. coli with an inactivation rate of 1.3 × 10^(-3) log reduction/cm min. The Fixed-Quat coated fiberglass mesh also demonstrated successful control of Microcystis aeruginosa with more than 99% inactivation after 10 hr of exposure.The developed antimicrobial mesh was also evaluated with wild-type microalgal species collected in a water body experiencing HABs, obtaining a 97% removal efficiency. Overall,the silica-functionalized Fixed-Quat nanocoating showed promising antimicrobial properties for water disinfection and HABs control, while decreasing concerns related to DBPs formation and the possible release of toxic nanomaterials into the environment.展开更多
Discovery and development of new sustainable photothermal materials with tunable light absorption spectra play a key role in solar energy harvesting and conversion.One possible solution to this quest is to check natur...Discovery and development of new sustainable photothermal materials with tunable light absorption spectra play a key role in solar energy harvesting and conversion.One possible solution to this quest is to check nature as a source of matters or inspiration.Inspired by the formation of tea stains,a unique class of dark stain materials generated by the interfacial reaction between tea polyphenols and metal substance,we reported the facile preparation and screening of a series of photothermal nanocoating layers via the metal ion(i.e.C u(ll)>Fe(lll),Ni(ll),Zn(ll))promoted in situ polymerization of typical phenolic moieties of tea polyphenols(i.e.,catechol and pyrogallol).It was found that those resulting metal-polyphenolic nanocoatings showed various promising features,such as high blackness and strong adhesion,excellent and tunable light absorption properties,good hydrophilicity and long-term stability.We further fabricated the photothermal composite devices by/n s/'fty formation of meta卜polyphenolic nanocoatings on pristine silks for solar desalination,which demonstrated promising durable evaporation behaviors with excellent evaporation rates and steam generation efficiencies.We believe that this work could provide more opportunities towards new types of bio-inspired and sustainable photothermal nanomaterials for solar energy harvesting applications such as water desalination.展开更多
Sulfide all-solid-state lithium batteries(SASSLBs)with a single-crystal nickel-rich layered oxide cathode(LiNix-CoyMn_(1-x-y)O_(2),x≥0.8)are highly desirable for advanced power batteries owing to their excellent ener...Sulfide all-solid-state lithium batteries(SASSLBs)with a single-crystal nickel-rich layered oxide cathode(LiNix-CoyMn_(1-x-y)O_(2),x≥0.8)are highly desirable for advanced power batteries owing to their excellent energy density and safety.Nevertheless,the cathode material's cracking issue and its severe interfacial problem with sulfide solid electrolytes have hindered the further development.This study proposes to employ surface modification engineering to produce B-NCM cathode materials coated with boride nanostructure stabilizer in situ by utilizing NCM encapsulated with residual lithium.This approach enhances the electrochemical performance of SASSLBs by effectively inhibiting electrochemical-mechanical degradation of the NCM cathode material on cycling and reducing deleterious side reactions with the solid sulfide electrolyte.The B-NCM/LPSCl/Gr SASSLBs demonstrate impressive cycling stability,retaining 84.19%of its capacity after 500 cycles at 0.2 C,which represents a 30.13%increase vs.NCM/LPSCl/Gr.It also exhibits a specific capacity of 170.4 mAh/g during its first discharge at 0.1 C.This work demonstrates an effective surface engineering strategy for enhancing capacity and cycle life,providing valuable insights into solving interfacial problems in SASSLBs.展开更多
纳米科学已涉及从信息学到地学的各个领域,成为这个时代一个标志性的关键词。近十多年来,国内外的纳米地学研究,在实践、理论和实验等诸方面都取得了迅速的进展。该文运用4F (Fact, Formation, Function and Formulation,即事实观察、...纳米科学已涉及从信息学到地学的各个领域,成为这个时代一个标志性的关键词。近十多年来,国内外的纳米地学研究,在实践、理论和实验等诸方面都取得了迅速的进展。该文运用4F (Fact, Formation, Function and Formulation,即事实观察、形成机理、功效作用和计算模拟)研究方法,利用扫描电子显微镜(SEM)和透射电子显微镜(TEM)对断裂剪切带中的纳米结构与成矿作用进行了样品观察和综合分析。首先,作者表述了岩石剪切面上广泛分布的剪切薄壳(膜)的形成、发育和组成,一般脆性剪切的薄壳厚度(h,毫米—厘米级)要比韧性的剪切薄膜(忽米—毫米级)厚,前者是由动态摩擦粘滑滑移引起的,而后者则是由静态蠕滑滑移造成的,且两者均是由纳米矿物和纳米结构组成的。随之,作者集中探讨了作为研究主体的剪切薄壳(膜)中纳米结构的应变变形和生成演化,它们既具有弹性又有粘性的变形特征而不是单一的力学属性。纳米结构的生成—发育—演化,可依剪切变形过程划分为强化(硬化)—弱化(软化)—脆化(退化)三个变形应变阶段,和相应的纳米涂层—纳米弱化—纳米层裂三种类型纳米作用:(1)纳米涂层是一种最基本的纳米作用,在成熟的断裂剪切(带)中,只要有滑移摩擦存在,就会有纳米结构。这种作用能引起有序的纳米结构和定向结构,包括单体纳米颗粒(通常直径d=40～80 nm)—复体纳米颗粒—多重复体纳米颗粒;纳米粒—纳米线—纳米层;纳米颗粒粒化—异化—再生等。(2)纳米弱化作用是由颗粒粒度减小,瞬时温热,叶理发育和弱势矿物等所致,并可细分为滑动纳米弱化、流变纳米弱化和动力纳米弱化三种类别。(3)纳米层裂作用是一种由动力热作用到静力冷作用诱发的剥离作用,通常沿着纳米结构的劈理面、解理和滑移面开裂。进而,以江西省的金山金矿和广丰滑石矿为例讨�展开更多
SnO2 electrodes have many advantages in the degradation of toxic or bio-refractory organic wastewater,and SnO2 is a kind of anode material which has the potential to be widely used.Electrocatalytic effi-ciency and ser...SnO2 electrodes have many advantages in the degradation of toxic or bio-refractory organic wastewater,and SnO2 is a kind of anode material which has the potential to be widely used.Electrocatalytic effi-ciency and service life of Ti\SnO2 electrodes are key factors that can influence its applications.In order to enhance the electrocatalytic characteristics of Ti\SnO2 electrodes,a type of electrocatalytic electrode with nanocoating was prepared by direct current(DC)electrodeposition method and thermal oxidation technique.With phenol as the model pollutant,the electrochemical degradation efficiencies of elec-trodes with nanocoating and non-nanocoating were investigated.It was demonstrated that the elec-trodes with nanocoating have higher efficiency than that of electrodes with non-nanocoating.The degradation time was decreased 33.3% for the same amount of phenol's degradation.The crystal structure of surface coating,the micrograph of electrode surface and the chemical environment of Sn and Sb in the electrode surface were analyzed with the help of XRD,SEM and XPS.The results showed that the surface of electrode was mainly SnO2 crystal with rutile structure and that much adsorbed oxygen in nanocoating was the dominant factor for enhancing the electrocatalytic characteristics.展开更多
One of the main problems of stainless steel is its poor pitting corrosion resistance in the aggressive environment containing Cl-, such as seawater. In this paper we investigated the corrosion behavior of the 316 stai...One of the main problems of stainless steel is its poor pitting corrosion resistance in the aggressive environment containing Cl-, such as seawater. In this paper we investigated the corrosion behavior of the 316 stainless steel coated by cerium oxide nanocoating prepared by sol-gel process. Potentiodynamic polarization and electrochemical impedance spectroscopy （EIS） were used to study the corrosion behavior of cerium oxide nanocoatings in 3.5% NaCl solution. The microstructure of the cerium oxide was examined by scanning electron microscopy （SEM） and the formed phases was identified by X-ray diffraction （XRD）. The pitting corrosion resistance of the cerium oxide nanocoating was found to be improved after heat treatment of the cerium oxide nanocoating at 300℃ for 30 min.展开更多
The aim of this study was to develop a method to prepare WO<sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span>&l...The aim of this study was to develop a method to prepare WO<sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> film which has high anticorrosion property when it was coated on type 304 stainless steel. A series of WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-modified TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sols were synthesized by peroxo-sol gel method using TiCl</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> and Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">WO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> as the starting materials. TiCl</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> was converted to Ti(OH)</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> gel. H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">WO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> were added in Ti(OH)</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> solution and heated at 95<span style="white-space:normal;">°</span>C. The WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sol was transparent, in neutral (pH^7) solution, stable suspension without surfactant, nano-c展开更多
A review of our experience in range of electron spectroscopy of the physical vapor-phase deposition and growth of single- and multilayer nanostructures with atomic scale interfaces is presented. The foundation of an i...A review of our experience in range of electron spectroscopy of the physical vapor-phase deposition and growth of single- and multilayer nanostructures with atomic scale interfaces is presented. The foundation of an innovative methodology for the combined AES-EELS analysis of layered nanostructures is developed. The methodology includes: 1) determination of the composition, thickness, and the mechanism of phase transitions in nanocoatings under the probing depth most appropriated for the range of film thickness 1 - 10 ML;2) quantitative iteration Auger-analysis of the composition, thickness and growth mechanism of nanocoating;3) structural and phase analysis of nanocoatings with use of the analysis of position, shape and energy of the plasmon EELS peak and with subtracting the contribution from the substrate;4) analysis of phase transitions with use of the shift of the plasmon Auger-satellite and 5) non-destructive profiling of the composition of nanocoatings over depth with use of a dependence of the intensity and energy of EELS peaks on the value of the primary electron energy.展开更多
Visible transparent yet low infrared-emissivity(ε)polymeric materials are highly anticipated in many applications,whereas the fabrication of which remains a formidable challenge.Herein,visible transparent,flexible,an...Visible transparent yet low infrared-emissivity(ε)polymeric materials are highly anticipated in many applications,whereas the fabrication of which remains a formidable challenge.Herein,visible transparent,flexible,and low-εpolymeric films were fabricated by nanocoating decoration of indium tin oxide(ITO)and MXene on polyethylene terephthalate(PET)film surface through magnetron sputtering and spray coating,respectively.The obtained PET-ITO@MXene(PET-IM)film exhibits lowεof 24.7%and high visible transmittance exceeding 50%,endowing it with excellent visible transparent infrared stealthy by reducing human skin radiation temperature from 32 to 20.8°C,and remarkable zero-energy passive radiative heating capability(5.7°C).Meanwhile,the transparent low-εPET-IM film has high solar absorptivity and electrical conductivity,enabling superior solar/electric to thermal conversion performance.Notably,the three heating modes of passive radiative and active solar/electric can be integrated together to cope with complex heating scenarios.These visible transparent low-εpolymeric films are highly promising in infrared stealth,building daylighting and thermal management,and personal precision heating.展开更多
Titanium and its alloys are commonly used as dental and bone implant materials.Biomimetic coating of titanium surfaces could improve their osteoinductive properties.In this work,we have developed a novel osteogenic co...Titanium and its alloys are commonly used as dental and bone implant materials.Biomimetic coating of titanium surfaces could improve their osteoinductive properties.In this work,we have developed a novel osteogenic composite nanocoating for titanium surfaces,which provides a natural environment for facilitating adhesion,proliferation,and osteogenic differentiation of bone marrow mesenchymal stem cells(MSCs).Electrospinning was used to produce composite nanofiber coatings based on polycaprolactone(PCL),nano-hydroxyapatite(nHAp)and strontium ranelate(SrRan).Thus,four types of coatings,i.e.,PCL,PCL/nHAp,PCL/SrRan,and PCL/nHAp/SrRan,were applied on titanium surfaces.To assess chemical,morphological and biological properties of the developed coatings,EDS,FTIR,XRD,XRF,SEM,AFM,in-vitro cytotoxicity and in-vitro hemocompatibility analyses were performed.Our findings have revealed that the composite nanocoatings were both cytocompatible and hemocompatible;thus PCL/HAp/SrRan composite nanofiber coating led to the highest cell viability.Osteogenic culture of MSCs on the nanocoatings led to the osteogenic differentiation of stem cells,confirmed by alkaline phosphatase activity and mineralization measurements.The findings support the notion that the proposed composite nanocoatings have the potential to promote new bone formation and enhance bone-implant integration.展开更多
基金The work was financially supported by the National Natural Science Foundation of China(Nos.51672146 and 21805157)the Natural Science Foundation of Shandong Province(No.ZR2018BEM011).
文摘High energy density and low-cost lithium-sulfur batteries have been considered as one of the most promising candidates for next-generation energy storage systems.However,the intrinsic problems of the sulfur cathode severely restrict their further practical application.Here,a unique double-shell architecture composed of hollow carbon spheres@interlayer-expanded and sulfur-enriched MoS2+x nanocoating composite has been developed as an efficient sulfur host.A uniform precursor coating derived from heteropolyanions-induced polymerization of pyrrole leads to space confinement effect during the in-situ sulfurization process,which generates the interlayer-expanded and sulfur-enriched MoS2+x nanosheets on amorphous carbon hollow spheres.This new sulfur host possesses multifarious merits including sufficient voids for loading sulfur active materials,high electronic conductivity,and fast lithium-ion diffusive pathways.In addition,additional active edge sites of MoS2+x accompanied by the nitrogen-doped carbon species endow the sulfur host with immobilizing and catalyzing effects on the soluble polysulfide species,dramatically accelerating their conversion kinetics and re-utilization.The detailed defect-induced interface catalytic reaction mechanism is firstly proposed.As expected,the delicately-designed sulfur host exhibits an outstanding initial discharge capacity of 1,249 mAh·g^−1 at 0.2 C and a desirable rate performance(593 mAh·g^−1 at 5.0 C),implying its great prospects in achieving superior electrochemical performances for advanced lithium sulfur batteries.
基金supported by Citrus Disease Research and Extension(CDRE)(grant no.2016-70016-24828/project accusation no.1008984)from the USDA National Institute of Food and Agriculture
文摘Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of receiving surface waters. Formation of unwanted disinfection by-products(DBPs) resulting from conventional disinfection technologies reveals the need for the development of new sustainable alternatives. Quaternary Ammonium Compounds(QACs) are cationic surfactants widely known for their effective biocidal properties at the ppm level. In this study, a novel silica-based antimicrobial nanofilm was developed using a composite of silica-modified QAC(Fixed-Quat) and applied to a fiberglass mesh as an active surface via sol–gel technique. The synthesized Fixed-Quat nanocoating was found to be effective against E. coli with an inactivation rate of 1.3 × 10^(-3) log reduction/cm min. The Fixed-Quat coated fiberglass mesh also demonstrated successful control of Microcystis aeruginosa with more than 99% inactivation after 10 hr of exposure.The developed antimicrobial mesh was also evaluated with wild-type microalgal species collected in a water body experiencing HABs, obtaining a 97% removal efficiency. Overall,the silica-functionalized Fixed-Quat nanocoating showed promising antimicrobial properties for water disinfection and HABs control, while decreasing concerns related to DBPs formation and the possible release of toxic nanomaterials into the environment.
基金the National Natural Science Foundation of China(Nos.21975167,21774079)the Program of the Science&Technology Department of Guangzhou,China(No.201803020039)the Fundamental Research Funds for Central Universities.
文摘Discovery and development of new sustainable photothermal materials with tunable light absorption spectra play a key role in solar energy harvesting and conversion.One possible solution to this quest is to check nature as a source of matters or inspiration.Inspired by the formation of tea stains,a unique class of dark stain materials generated by the interfacial reaction between tea polyphenols and metal substance,we reported the facile preparation and screening of a series of photothermal nanocoating layers via the metal ion(i.e.C u(ll)>Fe(lll),Ni(ll),Zn(ll))promoted in situ polymerization of typical phenolic moieties of tea polyphenols(i.e.,catechol and pyrogallol).It was found that those resulting metal-polyphenolic nanocoatings showed various promising features,such as high blackness and strong adhesion,excellent and tunable light absorption properties,good hydrophilicity and long-term stability.We further fabricated the photothermal composite devices by/n s/'fty formation of meta卜polyphenolic nanocoatings on pristine silks for solar desalination,which demonstrated promising durable evaporation behaviors with excellent evaporation rates and steam generation efficiencies.We believe that this work could provide more opportunities towards new types of bio-inspired and sustainable photothermal nanomaterials for solar energy harvesting applications such as water desalination.
基金support from the National Natural Science Foundation of China(Grant No.52374407)is gratefully acknowledged.
文摘Sulfide all-solid-state lithium batteries(SASSLBs)with a single-crystal nickel-rich layered oxide cathode(LiNix-CoyMn_(1-x-y)O_(2),x≥0.8)are highly desirable for advanced power batteries owing to their excellent energy density and safety.Nevertheless,the cathode material's cracking issue and its severe interfacial problem with sulfide solid electrolytes have hindered the further development.This study proposes to employ surface modification engineering to produce B-NCM cathode materials coated with boride nanostructure stabilizer in situ by utilizing NCM encapsulated with residual lithium.This approach enhances the electrochemical performance of SASSLBs by effectively inhibiting electrochemical-mechanical degradation of the NCM cathode material on cycling and reducing deleterious side reactions with the solid sulfide electrolyte.The B-NCM/LPSCl/Gr SASSLBs demonstrate impressive cycling stability,retaining 84.19%of its capacity after 500 cycles at 0.2 C,which represents a 30.13%increase vs.NCM/LPSCl/Gr.It also exhibits a specific capacity of 170.4 mAh/g during its first discharge at 0.1 C.This work demonstrates an effective surface engineering strategy for enhancing capacity and cycle life,providing valuable insights into solving interfacial problems in SASSLBs.
文摘纳米科学已涉及从信息学到地学的各个领域,成为这个时代一个标志性的关键词。近十多年来,国内外的纳米地学研究,在实践、理论和实验等诸方面都取得了迅速的进展。该文运用4F (Fact, Formation, Function and Formulation,即事实观察、形成机理、功效作用和计算模拟)研究方法,利用扫描电子显微镜(SEM)和透射电子显微镜(TEM)对断裂剪切带中的纳米结构与成矿作用进行了样品观察和综合分析。首先,作者表述了岩石剪切面上广泛分布的剪切薄壳(膜)的形成、发育和组成,一般脆性剪切的薄壳厚度(h,毫米—厘米级)要比韧性的剪切薄膜(忽米—毫米级)厚,前者是由动态摩擦粘滑滑移引起的,而后者则是由静态蠕滑滑移造成的,且两者均是由纳米矿物和纳米结构组成的。随之,作者集中探讨了作为研究主体的剪切薄壳(膜)中纳米结构的应变变形和生成演化,它们既具有弹性又有粘性的变形特征而不是单一的力学属性。纳米结构的生成—发育—演化,可依剪切变形过程划分为强化(硬化)—弱化(软化)—脆化(退化)三个变形应变阶段,和相应的纳米涂层—纳米弱化—纳米层裂三种类型纳米作用:(1)纳米涂层是一种最基本的纳米作用,在成熟的断裂剪切(带)中,只要有滑移摩擦存在,就会有纳米结构。这种作用能引起有序的纳米结构和定向结构,包括单体纳米颗粒(通常直径d=40～80 nm)—复体纳米颗粒—多重复体纳米颗粒;纳米粒—纳米线—纳米层;纳米颗粒粒化—异化—再生等。(2)纳米弱化作用是由颗粒粒度减小,瞬时温热,叶理发育和弱势矿物等所致,并可细分为滑动纳米弱化、流变纳米弱化和动力纳米弱化三种类别。(3)纳米层裂作用是一种由动力热作用到静力冷作用诱发的剥离作用,通常沿着纳米结构的劈理面、解理和滑移面开裂。进而,以江西省的金山金矿和广丰滑石矿为例讨�
基金Supported by the Excellence Young Teacher Foundation of China Educa-tion MinistryResearch Foundation for Outstanding Young Scholars of Heilongjiang Province(Grant No.JC-02-04)
文摘SnO2 electrodes have many advantages in the degradation of toxic or bio-refractory organic wastewater,and SnO2 is a kind of anode material which has the potential to be widely used.Electrocatalytic effi-ciency and service life of Ti\SnO2 electrodes are key factors that can influence its applications.In order to enhance the electrocatalytic characteristics of Ti\SnO2 electrodes,a type of electrocatalytic electrode with nanocoating was prepared by direct current(DC)electrodeposition method and thermal oxidation technique.With phenol as the model pollutant,the electrochemical degradation efficiencies of elec-trodes with nanocoating and non-nanocoating were investigated.It was demonstrated that the elec-trodes with nanocoating have higher efficiency than that of electrodes with non-nanocoating.The degradation time was decreased 33.3% for the same amount of phenol's degradation.The crystal structure of surface coating,the micrograph of electrode surface and the chemical environment of Sn and Sb in the electrode surface were analyzed with the help of XRD,SEM and XPS.The results showed that the surface of electrode was mainly SnO2 crystal with rutile structure and that much adsorbed oxygen in nanocoating was the dominant factor for enhancing the electrocatalytic characteristics.
基金supported by the Iranian Nanotechnology and Nanoscience Organization.
文摘One of the main problems of stainless steel is its poor pitting corrosion resistance in the aggressive environment containing Cl-, such as seawater. In this paper we investigated the corrosion behavior of the 316 stainless steel coated by cerium oxide nanocoating prepared by sol-gel process. Potentiodynamic polarization and electrochemical impedance spectroscopy （EIS） were used to study the corrosion behavior of cerium oxide nanocoatings in 3.5% NaCl solution. The microstructure of the cerium oxide was examined by scanning electron microscopy （SEM） and the formed phases was identified by X-ray diffraction （XRD）. The pitting corrosion resistance of the cerium oxide nanocoating was found to be improved after heat treatment of the cerium oxide nanocoating at 300℃ for 30 min.
文摘The aim of this study was to develop a method to prepare WO<sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> film which has high anticorrosion property when it was coated on type 304 stainless steel. A series of WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-modified TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sols were synthesized by peroxo-sol gel method using TiCl</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> and Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">WO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> as the starting materials. TiCl</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> was converted to Ti(OH)</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> gel. H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">WO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> were added in Ti(OH)</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> solution and heated at 95<span style="white-space:normal;">°</span>C. The WO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">-TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> sol was transparent, in neutral (pH^7) solution, stable suspension without surfactant, nano-c
文摘A review of our experience in range of electron spectroscopy of the physical vapor-phase deposition and growth of single- and multilayer nanostructures with atomic scale interfaces is presented. The foundation of an innovative methodology for the combined AES-EELS analysis of layered nanostructures is developed. The methodology includes: 1) determination of the composition, thickness, and the mechanism of phase transitions in nanocoatings under the probing depth most appropriated for the range of film thickness 1 - 10 ML;2) quantitative iteration Auger-analysis of the composition, thickness and growth mechanism of nanocoating;3) structural and phase analysis of nanocoatings with use of the analysis of position, shape and energy of the plasmon EELS peak and with subtracting the contribution from the substrate;4) analysis of phase transitions with use of the shift of the plasmon Auger-satellite and 5) non-destructive profiling of the composition of nanocoatings over depth with use of a dependence of the intensity and energy of EELS peaks on the value of the primary electron energy.
基金Financial support of the National Natural Science Foundation of China(No.52003248)the China Postdoctoral Science Foundation(Nos.2018M642780 and 2021T140613)+1 种基金the Opening Project of State Key Laboratory of Polymer Materials Engineering(Sichuan University)(No.sklpme2019-4-31)the Key Research and Development and Promotion projects of Henan Province(No.202102210032)are gratefully acknowledged.
文摘Visible transparent yet low infrared-emissivity(ε)polymeric materials are highly anticipated in many applications,whereas the fabrication of which remains a formidable challenge.Herein,visible transparent,flexible,and low-εpolymeric films were fabricated by nanocoating decoration of indium tin oxide(ITO)and MXene on polyethylene terephthalate(PET)film surface through magnetron sputtering and spray coating,respectively.The obtained PET-ITO@MXene(PET-IM)film exhibits lowεof 24.7%and high visible transmittance exceeding 50%,endowing it with excellent visible transparent infrared stealthy by reducing human skin radiation temperature from 32 to 20.8°C,and remarkable zero-energy passive radiative heating capability(5.7°C).Meanwhile,the transparent low-εPET-IM film has high solar absorptivity and electrical conductivity,enabling superior solar/electric to thermal conversion performance.Notably,the three heating modes of passive radiative and active solar/electric can be integrated together to cope with complex heating scenarios.These visible transparent low-εpolymeric films are highly promising in infrared stealth,building daylighting and thermal management,and personal precision heating.
文摘Titanium and its alloys are commonly used as dental and bone implant materials.Biomimetic coating of titanium surfaces could improve their osteoinductive properties.In this work,we have developed a novel osteogenic composite nanocoating for titanium surfaces,which provides a natural environment for facilitating adhesion,proliferation,and osteogenic differentiation of bone marrow mesenchymal stem cells(MSCs).Electrospinning was used to produce composite nanofiber coatings based on polycaprolactone(PCL),nano-hydroxyapatite(nHAp)and strontium ranelate(SrRan).Thus,four types of coatings,i.e.,PCL,PCL/nHAp,PCL/SrRan,and PCL/nHAp/SrRan,were applied on titanium surfaces.To assess chemical,morphological and biological properties of the developed coatings,EDS,FTIR,XRD,XRF,SEM,AFM,in-vitro cytotoxicity and in-vitro hemocompatibility analyses were performed.Our findings have revealed that the composite nanocoatings were both cytocompatible and hemocompatible;thus PCL/HAp/SrRan composite nanofiber coating led to the highest cell viability.Osteogenic culture of MSCs on the nanocoatings led to the osteogenic differentiation of stem cells,confirmed by alkaline phosphatase activity and mineralization measurements.The findings support the notion that the proposed composite nanocoatings have the potential to promote new bone formation and enhance bone-implant integration.
