NiMo-based materials have been identified as potential candidates of Pt/C electrocatalysts for hydrogen evolution reaction(HER)due to appropriate binding energy to hydrogen,and good resistance to corrosive environment...NiMo-based materials have been identified as potential candidates of Pt/C electrocatalysts for hydrogen evolution reaction(HER)due to appropriate binding energy to hydrogen,and good resistance to corrosive environments.However,little work has been carried out to enhance the catalytic performance in large-scale water-alkali electrolysis.The NoMo amorphous coating,as a highefficient and cost-effective catalyst toward HER,was synthesized by a facile electrodeposition strategy in this study.The effects of the pH value of electrolyte on the structure and HER activity of NiMo coating were investigated.The as-prepared NiMo_((pH10))exhibited the highest HER activity with overpotentials of 63.9 and 157.1 mV(vs.RHE,with 80%potential drop due to electrical resistance(iR)compensation)at the current density of-10 mA·cm^(-2)and-100 mA·cm^(-2).This NiMo_((pH10))coating also had excellent long-term durability of up to100 h stable operation under the constant current density of-100 mA·cm^(-2).The rapid HER kinetics and outstanding endurance can be ascribed to the NiMo compact coating with amorphous structures as well as good contact between NiMo coating and Ni foam substrate,endowing it grand feasibility in practical industrial applications.展开更多
The daily life of people in the intelligent age is inseparable from electronic device,and a number of bacteria on touch screens are increasingly threatening the health of users.Herein,a photocatalytic TiO_(2)/Ag thin ...The daily life of people in the intelligent age is inseparable from electronic device,and a number of bacteria on touch screens are increasingly threatening the health of users.Herein,a photocatalytic TiO_(2)/Ag thin film was synthesized on a glass by atomic layer deposition and subsequent in situ reduction.Ultraviolet-visible(UV-Vis)spectra showed that this film can harvest the simulated solar light more efficiently than that of pristine TiO_(2).The antibacterial tests in vitro showed that the antibacterial efficiency of the TiO_(2)/Ag film against S.aureus and E.coli was 98.2%and 98.6%,under visible light irradiation for 5 min.The underlying mechanism was that the in-situ reduction of Ag on the surface of TiO_(2)reduced the bandgap of TiO_(2)from 3.44 to 2.61 eV due to the formation of Schottky heterojunction at the interface between TiO_(2)and Ag.Thus,TiO_(2)/Ag can generate more reactive oxygen species for bacterial inactivation on the surface of electronic screens.More importantly,the TiO_(2)/Ag film had great biocompatibility with/without light irradiation.The platform not only provides a more convenient choice for the traditional antibacterial mode but also has limitless possibilities for application in the field of billions of touch screens.展开更多
Water splitting is an environment friendly and efficient way to produce hydrogen.Highly efficient and low-cost non-noble metal catalysts play an important role in hydrogen evolution reaction(HER).Dealloying is a simpl...Water splitting is an environment friendly and efficient way to produce hydrogen.Highly efficient and low-cost non-noble metal catalysts play an important role in hydrogen evolution reaction(HER).Dealloying is a simple method to prepare three-dimensional self-supporting nanoporous materials without conductive supports and binders.In this work,we prepared self-supporting nanoporous CoBP electrocatalyst by dealloying method.The influence of the synergistic effect of nonmetallic elements on catalytic activity was investigated.The synergistic electronic effect of Co,B and P atoms on the surface optimizes the H atoms desorption and results in superior HER activity.The bi-continuous structure of nanoporous CoBP provides more active area and favors of electron and electrolyte transfer.The nanoporous CoBP with the B/P atomic ratio of 1/3 exhibits low overpotential of 42 mV at 10 mA·cm^(-2),small Tafel slope of 39.8 mV·dec-1 and good long-term stability with no performance decrease for 20 h in alkaline solution.展开更多
Pathogenic bacteria have been threatening the daily life of human beings.More effective methods without causing drug-resistance of bacteria need to be developed to fight against these pathogens.Herein,flower-like CuS/...Pathogenic bacteria have been threatening the daily life of human beings.More effective methods without causing drug-resistance of bacteria need to be developed to fight against these pathogens.Herein,flower-like CuS/-graphene oxide(GO)hybrids have been successfully synthesized via simple one-pot hydrothermal process.GO worked as an excellent electron acceptor to transport the photogenerated electrons from CuS,which can suppress the recombination of hole–electron pairs efficiently,thus enhancing the photocatalytic property.In addition,the morphology of CuS and GO with high specific surface area and the increased defect in GO also improved photocatalytic performance of the hybrid.Owing to the synergy of photothermal,enhanced photocatalytic effect and released Cu ions,CuS/GO exhibited outstanding antibacterial efficacy under visible light irradiation for 15 min.Additionally,the hybrid showed great biocompatibility to L929 cell.Hence,the synthesized CuS/GO would be a promising antibacterial material for daily life including rapid water disinfection and wounds sterilization.展开更多
Because of the impressive evolution of the drugresistant bacteria,the development of efficient,antibioticfree agent is in great urgency.Herein,an efficient antibacterial agent,CuS@HKUST-polydopamine(PDA),was exquisite...Because of the impressive evolution of the drugresistant bacteria,the development of efficient,antibioticfree agent is in great urgency.Herein,an efficient antibacterial agent,CuS@HKUST-polydopamine(PDA),was exquisitely designed,where the Cu-based metal-organic framework(MOF)—HKUST nanoparticles served as the porous frame,and the CuS was synthesized within the structure of the MOF through the process of in situ sulfuration,followed with polydopamine(PDA)covering the nanoparticles.The structure of the HKUST preventing the aggregation of the CuS nanoparticles,which improved their photothermal and photocatalytic properties.After covering with PDA,the nanoparticles’abilities to produce heat and free radicals were further enhanced.This was because that the PDA itself could transform light into heat,which not only benefited the photothermal property,but also improved the photocatalytic property of the nanoparticles by accelerating the charge mobility.Moreover,the PDA could also transfer the photo-induced electrons fast and thus prevented the recombination of the photo-generated electron–hole pairs,which resulted in the enhanced ability to produce free radicals.As a result,under light irradiation,the antibacterial efficiency of the CuS@HKUST-PDA against Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)could reach 99.77%and 99.57%.Hence,the synthesized CuS@HKUST-PDA can be promising for anti-infection and sterilization application without using antibiotics.展开更多
Controlling the corrosion rate is critical for practical applications of Mg-based alloys. In this work, we constructed a protective coating of hybrid polycaprolactone(H-PCL)/indocyanine green(ICG) on AZ31 Mg alloy,who...Controlling the corrosion rate is critical for practical applications of Mg-based alloys. In this work, we constructed a protective coating of hybrid polycaprolactone(H-PCL)/indocyanine green(ICG) on AZ31 Mg alloy,whose degradation rate was controlled by 808-nm nearinfrared(NIR) light irradiation. The corrosion behaviors of H-PCL/ICG coated Mg alloys were systematically investigated by potentiodynamic polarization tests, electrochemical impedance spectroscopy(EIS) and hydrogen evolution experiments. The results disclosed that the H-PCL/ICG composite coating could effectively protect Mg alloy from corroding without NIR light irradiation. In contrast, under 808-nm NIR light irradiation, the corrosion resistance of this composite coating was decreased significantly, i.e., the corrosion current density(i_(corr))increasedfrom(8.81 ± 1.068) 9 10^(-8) to(1.22 ± 0.545) 9 10^(-6) A·cm^(-2). This is because the component of ICG in the coating was excited to produce heat locally, which triggered the glass transition temperature(T_(g)) of H-PCL in the coating, resulting in the motion of the molecular chain segment. Consequently, the electrolytes penetrated the coating and corroded the Mg substrate. In vitro biological experiment indicated that the synthesized coating exhibited good cytocompatibility.Hence, these findings will provide a new strategy for designing novel photoresponsive coatings to remotely adjust the degradation rate of biodegradable metals for biomedical applications.展开更多
Deep tissue infections caused by pathogenic bacteria seriously threat the lives of patients.In this study a smart heterostructured Au/Cu-BTA(BTA=1,2,4,5-benzenetetramine)with microwave(MW)response is synthesized via N...Deep tissue infections caused by pathogenic bacteria seriously threat the lives of patients.In this study a smart heterostructured Au/Cu-BTA(BTA=1,2,4,5-benzenetetramine)with microwave(MW)response is synthesized via NaBH_(4)reduction of HAuCl_(4)on the Cu-BTA.Au/Cu-BTA exhibits excellent hyperthermy and dynamics under MW irradiation.The MW thermal mechanism of Au/Cu-BTA is attributed to the excellen dielectric loss and polarization of the heterogeneous interface.Meanwhile,the surface energy levels of the Cu-BTA interface alleviate the difficulty of electron hopping through multistage transition.Therefore,MW can excite Cu-BTA to produce free electrons.Subsequently,Au nanoparticles rapidly increase electron transfer and inhibit electron-hole recombination.Hence,the yields of reactive oxygen species can be enhanced for MW dynamic therapy Consequently,under 10 min of MW irradiation,Au/Cu-BTA killed 99.998%±0.001% of Gram-positive Staphylococcus aureus,99.966%±0.014% of methicillin-resistant Staphylococcus aureus,and 96.871%±0.831% of Gram-negative Pseudomonas aeruginosa.The effective MW bacteria-killing strategy designed in this study shows significant potential for application in the MW-responsive treatment of deep tissue infections without antibiotics.展开更多
Biomedical metal materials such as titanium, magnesium and their alloys have been widely studied as orthopedic implants or cardiovascular stents due to their desirable mechanical properties and excellent biocompatibil...Biomedical metal materials such as titanium, magnesium and their alloys have been widely studied as orthopedic implants or cardiovascular stents due to their desirable mechanical properties and excellent biocompatibility.However, these metal implants still exist some problems in practical application including bacterial infection, lack of bioactivity, and uncontrolled corrosion behaviors. Toaddress these problems, the performance of these metallicimplants can be improved through surface modification andincorporating alloying elements into raw materials ofimplants.展开更多
Recently,the issue of bacterial resistance has gotten worse because of the overuse of antibiotics.The newborn superbacteria,such as vancomycin-resistant bacteria,were hard to kill,inspiring researchers to find new way...Recently,the issue of bacterial resistance has gotten worse because of the overuse of antibiotics.The newborn superbacteria,such as vancomycin-resistant bacteria,were hard to kill,inspiring researchers to find new ways to kill the bacteria efficiently.TiO_(2) was used as an efficient photocatalyst for water split-ting and pollutant degradation.However,the weak efficiency limited the application to solve the drug-resistance problem.Consequently,the incorpora-tion of low-cost 0D carbon quantum dots(CQDs)and 2D graphene oxide(GO)was pursued to amplify the visible light absorption capabilities of TiO_(2) and thereby elevate its photocatalytic activity.After forming the heterogeneous interface of CQDs and TiO_(2),CQDs converted part of visible light into wave-length less than 400 nm using the up-conversion property.The modification of CQDs enabled electrons to be easily transferred from the conduction band of CQDs to the conduction band of TiO_(2).Meanwhile,GO can act as an electron acceptor,reduce the recombination efficiency of holes and electrons,and transfer the photogenerated electrons in the redox reaction in the heterogeneous interface.Because of the excellent absorption of GO,TiO_(2)/CQDs/GO reached 57.8℃after 20 min irradiation under 1.5 times sunlight,which provided a prerequisite for photodynamic antibacterial therapy/photothermal antibacterial therapy synergistic antibacterial potential.TiO_(2)/CQDs/GO possessed an anti-bacterial efficiency as high as 99.3%toward Staphylococcus aureus which has a bright future in disinfection in vivo and medical devices as well as water sterilization.展开更多
基金financially supported by the National Natural Science Foundation of China (No.51771131)
文摘NiMo-based materials have been identified as potential candidates of Pt/C electrocatalysts for hydrogen evolution reaction(HER)due to appropriate binding energy to hydrogen,and good resistance to corrosive environments.However,little work has been carried out to enhance the catalytic performance in large-scale water-alkali electrolysis.The NoMo amorphous coating,as a highefficient and cost-effective catalyst toward HER,was synthesized by a facile electrodeposition strategy in this study.The effects of the pH value of electrolyte on the structure and HER activity of NiMo coating were investigated.The as-prepared NiMo_((pH10))exhibited the highest HER activity with overpotentials of 63.9 and 157.1 mV(vs.RHE,with 80%potential drop due to electrical resistance(iR)compensation)at the current density of-10 mA·cm^(-2)and-100 mA·cm^(-2).This NiMo_((pH10))coating also had excellent long-term durability of up to100 h stable operation under the constant current density of-100 mA·cm^(-2).The rapid HER kinetics and outstanding endurance can be ascribed to the NiMo compact coating with amorphous structures as well as good contact between NiMo coating and Ni foam substrate,endowing it grand feasibility in practical industrial applications.
基金financially supported by the National Natural Science Foundation of China(Nos.82002303,51871162 and 51932002)the China National Funds for Distinguished Young Scientists(No.51925104)+2 种基金Scientific Research Foundation of Peking University Shenzhen Hospital(No.KYQD2021064)Beijing Municipal Health Commission(Nos.BMHC-2021-6,BMHC-2019-9,BMHC-2018-4 and PXM2020_026275_000002)the National Key R&D Program of China(No.R&D#2018YFA0703100)
文摘The daily life of people in the intelligent age is inseparable from electronic device,and a number of bacteria on touch screens are increasingly threatening the health of users.Herein,a photocatalytic TiO_(2)/Ag thin film was synthesized on a glass by atomic layer deposition and subsequent in situ reduction.Ultraviolet-visible(UV-Vis)spectra showed that this film can harvest the simulated solar light more efficiently than that of pristine TiO_(2).The antibacterial tests in vitro showed that the antibacterial efficiency of the TiO_(2)/Ag film against S.aureus and E.coli was 98.2%and 98.6%,under visible light irradiation for 5 min.The underlying mechanism was that the in-situ reduction of Ag on the surface of TiO_(2)reduced the bandgap of TiO_(2)from 3.44 to 2.61 eV due to the formation of Schottky heterojunction at the interface between TiO_(2)and Ag.Thus,TiO_(2)/Ag can generate more reactive oxygen species for bacterial inactivation on the surface of electronic screens.More importantly,the TiO_(2)/Ag film had great biocompatibility with/without light irradiation.The platform not only provides a more convenient choice for the traditional antibacterial mode but also has limitless possibilities for application in the field of billions of touch screens.
基金financially supported by the National Natural Science Foundation of China(No.51771131)。
文摘Water splitting is an environment friendly and efficient way to produce hydrogen.Highly efficient and low-cost non-noble metal catalysts play an important role in hydrogen evolution reaction(HER).Dealloying is a simple method to prepare three-dimensional self-supporting nanoporous materials without conductive supports and binders.In this work,we prepared self-supporting nanoporous CoBP electrocatalyst by dealloying method.The influence of the synergistic effect of nonmetallic elements on catalytic activity was investigated.The synergistic electronic effect of Co,B and P atoms on the surface optimizes the H atoms desorption and results in superior HER activity.The bi-continuous structure of nanoporous CoBP provides more active area and favors of electron and electrolyte transfer.The nanoporous CoBP with the B/P atomic ratio of 1/3 exhibits low overpotential of 42 mV at 10 mA·cm^(-2),small Tafel slope of 39.8 mV·dec-1 and good long-term stability with no performance decrease for 20 h in alkaline solution.
基金This work was financially supported by the National Science Fund for Distinguished Young Scholars(No.51925104)the National Natural Science Foundation of China(Nos.51871162 and 51671081)。
文摘Pathogenic bacteria have been threatening the daily life of human beings.More effective methods without causing drug-resistance of bacteria need to be developed to fight against these pathogens.Herein,flower-like CuS/-graphene oxide(GO)hybrids have been successfully synthesized via simple one-pot hydrothermal process.GO worked as an excellent electron acceptor to transport the photogenerated electrons from CuS,which can suppress the recombination of hole–electron pairs efficiently,thus enhancing the photocatalytic property.In addition,the morphology of CuS and GO with high specific surface area and the increased defect in GO also improved photocatalytic performance of the hybrid.Owing to the synergy of photothermal,enhanced photocatalytic effect and released Cu ions,CuS/GO exhibited outstanding antibacterial efficacy under visible light irradiation for 15 min.Additionally,the hybrid showed great biocompatibility to L929 cell.Hence,the synthesized CuS/GO would be a promising antibacterial material for daily life including rapid water disinfection and wounds sterilization.
基金This work was financially supported by Jilin Provincial Science and Technology Project(No.YDZJ202101-ZYTS054)the National Science Fund for Distinguished Young Scholars(No.51925104)the National Natural Science Foundation of China(No.51871162).
文摘Because of the impressive evolution of the drugresistant bacteria,the development of efficient,antibioticfree agent is in great urgency.Herein,an efficient antibacterial agent,CuS@HKUST-polydopamine(PDA),was exquisitely designed,where the Cu-based metal-organic framework(MOF)—HKUST nanoparticles served as the porous frame,and the CuS was synthesized within the structure of the MOF through the process of in situ sulfuration,followed with polydopamine(PDA)covering the nanoparticles.The structure of the HKUST preventing the aggregation of the CuS nanoparticles,which improved their photothermal and photocatalytic properties.After covering with PDA,the nanoparticles’abilities to produce heat and free radicals were further enhanced.This was because that the PDA itself could transform light into heat,which not only benefited the photothermal property,but also improved the photocatalytic property of the nanoparticles by accelerating the charge mobility.Moreover,the PDA could also transfer the photo-induced electrons fast and thus prevented the recombination of the photo-generated electron–hole pairs,which resulted in the enhanced ability to produce free radicals.As a result,under light irradiation,the antibacterial efficiency of the CuS@HKUST-PDA against Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)could reach 99.77%and 99.57%.Hence,the synthesized CuS@HKUST-PDA can be promising for anti-infection and sterilization application without using antibiotics.
基金jointly supported by the Natural Science Fund of Hubei Province(No.2018CFA064)the National Natural Science Foundation of China(Nos.51871162 and 51671081)+3 种基金the National Science Fund for Distinguished Young Scholars(No.51925104)the Key Program of National Natural Science Foundation of China(No.51631007)Hong Kong ITC(Nos.ITS/287/17 and GHX/002/14SZ)the Health and Medical Research Fund(No.03142446)。
文摘Controlling the corrosion rate is critical for practical applications of Mg-based alloys. In this work, we constructed a protective coating of hybrid polycaprolactone(H-PCL)/indocyanine green(ICG) on AZ31 Mg alloy,whose degradation rate was controlled by 808-nm nearinfrared(NIR) light irradiation. The corrosion behaviors of H-PCL/ICG coated Mg alloys were systematically investigated by potentiodynamic polarization tests, electrochemical impedance spectroscopy(EIS) and hydrogen evolution experiments. The results disclosed that the H-PCL/ICG composite coating could effectively protect Mg alloy from corroding without NIR light irradiation. In contrast, under 808-nm NIR light irradiation, the corrosion resistance of this composite coating was decreased significantly, i.e., the corrosion current density(i_(corr))increasedfrom(8.81 ± 1.068) 9 10^(-8) to(1.22 ± 0.545) 9 10^(-6) A·cm^(-2). This is because the component of ICG in the coating was excited to produce heat locally, which triggered the glass transition temperature(T_(g)) of H-PCL in the coating, resulting in the motion of the molecular chain segment. Consequently, the electrolytes penetrated the coating and corroded the Mg substrate. In vitro biological experiment indicated that the synthesized coating exhibited good cytocompatibility.Hence, these findings will provide a new strategy for designing novel photoresponsive coatings to remotely adjust the degradation rate of biodegradable metals for biomedical applications.
基金financially supported by the China National Funds for Distinguished Young Scientists(No.51925104)the National Natural Science Foundation of China(No.52173251)+2 种基金NSFC-Guangdong Province Joint Program(Key program No.U21A2084)the Central Guidance on Local Science and Technology Development Fund of Hebei Province(No.226Z1303G)Yanzhao Young Scientist Project(No.C2023202018)and Beijing Natural Science Foundation(No.7232338)。
文摘Deep tissue infections caused by pathogenic bacteria seriously threat the lives of patients.In this study a smart heterostructured Au/Cu-BTA(BTA=1,2,4,5-benzenetetramine)with microwave(MW)response is synthesized via NaBH_(4)reduction of HAuCl_(4)on the Cu-BTA.Au/Cu-BTA exhibits excellent hyperthermy and dynamics under MW irradiation.The MW thermal mechanism of Au/Cu-BTA is attributed to the excellen dielectric loss and polarization of the heterogeneous interface.Meanwhile,the surface energy levels of the Cu-BTA interface alleviate the difficulty of electron hopping through multistage transition.Therefore,MW can excite Cu-BTA to produce free electrons.Subsequently,Au nanoparticles rapidly increase electron transfer and inhibit electron-hole recombination.Hence,the yields of reactive oxygen species can be enhanced for MW dynamic therapy Consequently,under 10 min of MW irradiation,Au/Cu-BTA killed 99.998%±0.001% of Gram-positive Staphylococcus aureus,99.966%±0.014% of methicillin-resistant Staphylococcus aureus,and 96.871%±0.831% of Gram-negative Pseudomonas aeruginosa.The effective MW bacteria-killing strategy designed in this study shows significant potential for application in the MW-responsive treatment of deep tissue infections without antibiotics.
文摘Biomedical metal materials such as titanium, magnesium and their alloys have been widely studied as orthopedic implants or cardiovascular stents due to their desirable mechanical properties and excellent biocompatibility.However, these metal implants still exist some problems in practical application including bacterial infection, lack of bioactivity, and uncontrolled corrosion behaviors. Toaddress these problems, the performance of these metallicimplants can be improved through surface modification andincorporating alloying elements into raw materials ofimplants.
基金supported by the China National Funds for Distinguished Young Scientists(No.51925104)the National Natural Science Foundation of China(NSFC)(No.52173251)+3 种基金NSFC-Guangdong Province Joint Program(Key program No.U21A2084)Yanzhao Young Scientist Project(No.C2023202018)Beijing Natural Science Foundation(No.7232338)the Central Guidance on Local Science and Technology Development Fund of Hebei Province(No.226Z1303G).
文摘Recently,the issue of bacterial resistance has gotten worse because of the overuse of antibiotics.The newborn superbacteria,such as vancomycin-resistant bacteria,were hard to kill,inspiring researchers to find new ways to kill the bacteria efficiently.TiO_(2) was used as an efficient photocatalyst for water split-ting and pollutant degradation.However,the weak efficiency limited the application to solve the drug-resistance problem.Consequently,the incorpora-tion of low-cost 0D carbon quantum dots(CQDs)and 2D graphene oxide(GO)was pursued to amplify the visible light absorption capabilities of TiO_(2) and thereby elevate its photocatalytic activity.After forming the heterogeneous interface of CQDs and TiO_(2),CQDs converted part of visible light into wave-length less than 400 nm using the up-conversion property.The modification of CQDs enabled electrons to be easily transferred from the conduction band of CQDs to the conduction band of TiO_(2).Meanwhile,GO can act as an electron acceptor,reduce the recombination efficiency of holes and electrons,and transfer the photogenerated electrons in the redox reaction in the heterogeneous interface.Because of the excellent absorption of GO,TiO_(2)/CQDs/GO reached 57.8℃after 20 min irradiation under 1.5 times sunlight,which provided a prerequisite for photodynamic antibacterial therapy/photothermal antibacterial therapy synergistic antibacterial potential.TiO_(2)/CQDs/GO possessed an anti-bacterial efficiency as high as 99.3%toward Staphylococcus aureus which has a bright future in disinfection in vivo and medical devices as well as water sterilization.
