The high activity of metallic magnesium and alloys limits its potential in biomedical applications;in recent years,extensive efforts have been devoted to modulating this reactivity.In this work,we present Mg(OH)_(2) a...The high activity of metallic magnesium and alloys limits its potential in biomedical applications;in recent years,extensive efforts have been devoted to modulating this reactivity.In this work,we present Mg(OH)_(2) and TiO_(2)barrier coatings to reduce the degradation of magnesium alloy(Mg-Ca-Zn)surfaces.These coatings were deposited by the anodization method and the spin-coating technique,respectively.The anodized layer was coated with TiO_(2)generated from the hydrolysis of 3%weight of TTIP(Ti[OCH(CH_(3))_(2)]_(4),Titanium(IV)isopropoxide)in 2-Propanol deposited by the spin-coating method.Studying the degradation in Ringer’s solution by electrochemical impedance spectroscopy and OCP revealed a 98%reduction in pittings in uncoated samples after 14 days of immersion.The p H measurements revealed that the TiO_(2)coating reduced the alkalization of the physiological environment,keeping the pH at 6.0 values.In vitro studies of two types of bacteria(E.coli and S.aureus)exhibited zones of inhibition in the agar and activity bactericidal(kill time test).The mechanisms behind the improved degradation resistance and enhanced antibacterial activity are presented and discussed here.Surface modification with Mg(OH)_(2)/TiO_(2)coatings is a promising strategy to control the biodegradation of magnesium implants for bone regeneration.展开更多
Bromine has attracted significant attention as a cathode material for aqueous batteries due to its high reduction potential of 1.05 V(Br_(3)^(-)+2e~-■3Br~-),impressive theoretical specific capacity of 223 mA h g^(-1)...Bromine has attracted significant attention as a cathode material for aqueous batteries due to its high reduction potential of 1.05 V(Br_(3)^(-)+2e~-■3Br~-),impressive theoretical specific capacity of 223 mA h g^(-1),and rapid reaction kinetics in the electrolyte.However,searching for compatible anode materials to match with bromine has posed a challenge due to its highly corrosive nature.In this study,we developed oxygen-deficient MoO_(3) with TiO_(2) coating(referred to as MoO_(3-x)@TiO_(2))as an anode material to pair with a bromine cathode in static full batteries.The oxygen deficiency contributes to enhanced electronic and protonic diffusion within the MoO_(3-x)lattice,while the TiO_(2) coating mitigates structural dissolution and proton trapping during cycling.The MoO_(3-x)@TiO_(2) demonstrates fast charge storage kinetics and excellent resistance to bromine corrosion.The impressive compatibility between MoO_(3-x)@TiO_(2) and bromine enables the construction of membrane-less full batteries with exceptional rate capability and cyclic stability.The MoO_(3-x)@TiO_(2)-bromine battery achieves an energy density of70.8 W h kg^(-1)at a power density of 328.1 W kg^(-1),showcasing an impressive long-term cyclic life of 20,000 cycles.Our study provides valuable insights for the development of high-performance aqueous secondary batteries.展开更多
The titanium coatings were prepared on Al_(2)O_(3) balls by mechanical coating technique (MCT),and then the coatings were oxidized to titanium oxides(TiO_(2)) films at 300-600 ℃.The effects of different milling time ...The titanium coatings were prepared on Al_(2)O_(3) balls by mechanical coating technique (MCT),and then the coatings were oxidized to titanium oxides(TiO_(2)) films at 300-600 ℃.The effects of different milling time and oxidation temperature on thickness of films were studied.The composition and microstructure of the films were analyzed by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS).The results show that the thickest coatings with an average thickness of 20 μm were obtained at the milling time of 15 h.In addition,with the increase of the oxidation temperature,the oxidation of the film is increased.When the milling time is 15 h,the oxidation temperature is 500 ℃,and the addition of photocatalyst is 1 g/mL.The films have the best photocatalytic performance when the degradation rate of methyl orange solution reaches the maximum value of 74.9 %,and the films have a good reusability.展开更多
The"one pot"simultaneous carbon coating and doping of TiO_(2) materials by the hydrolysis of TiCl4 in fructose is reported.The synergistic effect of carbon doping and coating of TiO_(2) to significantly boos...The"one pot"simultaneous carbon coating and doping of TiO_(2) materials by the hydrolysis of TiCl4 in fructose is reported.The synergistic effect of carbon doping and coating of TiO_(2) to significantly boost textural,optical and electronic properties and photocurrent of TiO_(2) for high performance visible light H2 production from water splitting has been comprehensively investigated.Carbon doping can significantly increase the thermal stability,thus inhibiting the phase transformation of the Titania material from anatase to rutile while carbon coating can suppress the grain aggregation of TiO_(2).The synergy of carbon doping and coating can not only ensure an enhanced narrowing effect of the electronic band gap of TiO_(2) thus extending the absorption of photocatalysts to the visible regions,but also promote dramatically the separation of electron-hole pairs.Owing to these synergistic effects,the carbon coated and doped TiO_(2) shows much superior photocatalytic activity for both degradation of organics and photocatalytic/photoelectro chemical(PEC)water splitting under simulated sunlight illumination.The photocatalytic activity of obtained materials can reach 5,4 and 2 times higher than that of pristine TiO_(2),carbon doped TiO_(2) and carbon coated TiO_(2),respectively in the degradation of organic pollutants.The carbon coated and doped TiO_(2) materials exhibited more than 37 times and hundreds of times photocurrent enhancement under simulated sunlight and visible light,respectively compared to that of pristine TiO_(2).The present work providing new comprehensive understanding on carbon coating and doping effect could be very helpful for the development of advanced TiO_(2) materials for a large series of applications.展开更多
The interface and quality of TiO_2 coated optical fiber,which is obtained by dipping nude fibers into TiO_2 slurry,were investigated. The coating processes were carried out under different designed conditions,includin...The interface and quality of TiO_2 coated optical fiber,which is obtained by dipping nude fibers into TiO_2 slurry,were investigated. The coating processes were carried out under different designed conditions,including various adhesives,solid content of TiO_2 slurry,times of cladding and followed heat-treat temperature. The interface and coating qualities were observed by scanning electron microscope. Coating defects,such as cracking,breaking off and the inhomogeneity of the cladding corresponds to different coating condition were analyzed. As a result, a well-combined and durable TiO_2 coating in optical fiber surface was obtained under definite optimizing experimental conditions and parameters.展开更多
基金financed by the FOMIX-Yucatán 2008-108160,CONACYT LAB-2009-01-123913,292692,294643,188345,and 204822 projectsthe financial support received from CONACYT。
文摘The high activity of metallic magnesium and alloys limits its potential in biomedical applications;in recent years,extensive efforts have been devoted to modulating this reactivity.In this work,we present Mg(OH)_(2) and TiO_(2)barrier coatings to reduce the degradation of magnesium alloy(Mg-Ca-Zn)surfaces.These coatings were deposited by the anodization method and the spin-coating technique,respectively.The anodized layer was coated with TiO_(2)generated from the hydrolysis of 3%weight of TTIP(Ti[OCH(CH_(3))_(2)]_(4),Titanium(IV)isopropoxide)in 2-Propanol deposited by the spin-coating method.Studying the degradation in Ringer’s solution by electrochemical impedance spectroscopy and OCP revealed a 98%reduction in pittings in uncoated samples after 14 days of immersion.The p H measurements revealed that the TiO_(2)coating reduced the alkalization of the physiological environment,keeping the pH at 6.0 values.In vitro studies of two types of bacteria(E.coli and S.aureus)exhibited zones of inhibition in the agar and activity bactericidal(kill time test).The mechanisms behind the improved degradation resistance and enhanced antibacterial activity are presented and discussed here.Surface modification with Mg(OH)_(2)/TiO_(2)coatings is a promising strategy to control the biodegradation of magnesium implants for bone regeneration.
基金the financial support from the National Key Research and Development Program of China(2022YFB2502003)the Guangdong Basic and Applied Basic Research Foundation(2023B1515040011)。
文摘Bromine has attracted significant attention as a cathode material for aqueous batteries due to its high reduction potential of 1.05 V(Br_(3)^(-)+2e~-■3Br~-),impressive theoretical specific capacity of 223 mA h g^(-1),and rapid reaction kinetics in the electrolyte.However,searching for compatible anode materials to match with bromine has posed a challenge due to its highly corrosive nature.In this study,we developed oxygen-deficient MoO_(3) with TiO_(2) coating(referred to as MoO_(3-x)@TiO_(2))as an anode material to pair with a bromine cathode in static full batteries.The oxygen deficiency contributes to enhanced electronic and protonic diffusion within the MoO_(3-x)lattice,while the TiO_(2) coating mitigates structural dissolution and proton trapping during cycling.The MoO_(3-x)@TiO_(2) demonstrates fast charge storage kinetics and excellent resistance to bromine corrosion.The impressive compatibility between MoO_(3-x)@TiO_(2) and bromine enables the construction of membrane-less full batteries with exceptional rate capability and cyclic stability.The MoO_(3-x)@TiO_(2)-bromine battery achieves an energy density of70.8 W h kg^(-1)at a power density of 328.1 W kg^(-1),showcasing an impressive long-term cyclic life of 20,000 cycles.Our study provides valuable insights for the development of high-performance aqueous secondary batteries.
基金Funded by University-level Project of Jincheng College of Sichuan University(No.2020jcky0014)。
文摘The titanium coatings were prepared on Al_(2)O_(3) balls by mechanical coating technique (MCT),and then the coatings were oxidized to titanium oxides(TiO_(2)) films at 300-600 ℃.The effects of different milling time and oxidation temperature on thickness of films were studied.The composition and microstructure of the films were analyzed by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS).The results show that the thickest coatings with an average thickness of 20 μm were obtained at the milling time of 15 h.In addition,with the increase of the oxidation temperature,the oxidation of the film is increased.When the milling time is 15 h,the oxidation temperature is 500 ℃,and the addition of photocatalyst is 1 g/mL.The films have the best photocatalytic performance when the degradation rate of methyl orange solution reaches the maximum value of 74.9 %,and the films have a good reusability.
基金supported by the National Natural Science Foundation of China(U1663225,21805280)Program for Changjiang Scholars and Innovative Research Team in University(IRT15R52)+2 种基金the Minstry of Education of Chinathe 111 Project(Grant No.B20002)from the Ministry of Science and Technology and the Ministry of Education of China,China,European Commission,Interreg V France-Wallonie-Vlaanderen(Depollutair)the Fundamental Research Funds for the Central Universities(WUT:2017III001),Chinathe FJIRSM&IUE Joint Research Fund(RHZX-2018-002),China for supporting this work。
文摘The"one pot"simultaneous carbon coating and doping of TiO_(2) materials by the hydrolysis of TiCl4 in fructose is reported.The synergistic effect of carbon doping and coating of TiO_(2) to significantly boost textural,optical and electronic properties and photocurrent of TiO_(2) for high performance visible light H2 production from water splitting has been comprehensively investigated.Carbon doping can significantly increase the thermal stability,thus inhibiting the phase transformation of the Titania material from anatase to rutile while carbon coating can suppress the grain aggregation of TiO_(2).The synergy of carbon doping and coating can not only ensure an enhanced narrowing effect of the electronic band gap of TiO_(2) thus extending the absorption of photocatalysts to the visible regions,but also promote dramatically the separation of electron-hole pairs.Owing to these synergistic effects,the carbon coated and doped TiO_(2) shows much superior photocatalytic activity for both degradation of organics and photocatalytic/photoelectro chemical(PEC)water splitting under simulated sunlight illumination.The photocatalytic activity of obtained materials can reach 5,4 and 2 times higher than that of pristine TiO_(2),carbon doped TiO_(2) and carbon coated TiO_(2),respectively in the degradation of organic pollutants.The carbon coated and doped TiO_(2) materials exhibited more than 37 times and hundreds of times photocurrent enhancement under simulated sunlight and visible light,respectively compared to that of pristine TiO_(2).The present work providing new comprehensive understanding on carbon coating and doping effect could be very helpful for the development of advanced TiO_(2) materials for a large series of applications.
文摘The interface and quality of TiO_2 coated optical fiber,which is obtained by dipping nude fibers into TiO_2 slurry,were investigated. The coating processes were carried out under different designed conditions,including various adhesives,solid content of TiO_2 slurry,times of cladding and followed heat-treat temperature. The interface and coating qualities were observed by scanning electron microscope. Coating defects,such as cracking,breaking off and the inhomogeneity of the cladding corresponds to different coating condition were analyzed. As a result, a well-combined and durable TiO_2 coating in optical fiber surface was obtained under definite optimizing experimental conditions and parameters.
