Defect engineering can give birth to novel properties for adsorption and photocatalysis in the control of antibiotics and heavy metal combined pollution with photocatalytic composites.However,the role of defects and t...Defect engineering can give birth to novel properties for adsorption and photocatalysis in the control of antibiotics and heavy metal combined pollution with photocatalytic composites.However,the role of defects and the process mechanism are complicated and indefinable.Herein,TiO_(2)/CN/3DC was fabricated and defects were introduced into the tripartite structure with separate O_(2)plasma treatment for the single component.We find that defect engineering can improve the photocatalytic activity,attributing to the increase of the contribution from h^(+)and OH.In contrast to TiO_(2)/CN/3DC with a photocatalytic tetracycline removal rate of 75.2%,the removal rate of TC with D-TiO_(2)/CN/3DC has increased to 88.5%.Moreover,the reactive sites of tetracycline can be increased by adsorbing on the defective composites.The defect construction on TiO_(2)shows the advantages in tetracycline degradation and Cu^(2+)adsorption,but also suffers significant inhibition for the tetracycline degradation in a tetracycline/Cu^(2+)combined system.In contrast,the defect construction on graphene can achieve the cooperative removal of tetracycline and Cu^(2+).These findings can provide new insights into water treatment strategies with defect engineering.展开更多
MgSO4 is chosen as an additive to address the capacity fading issue in the rechargeable zinc-ion battery system of MgxV2O5·nH2O//ZnSO4//zinc.Electrolytes with different concentration ratios of ZnSO4 and MgSO4 are...MgSO4 is chosen as an additive to address the capacity fading issue in the rechargeable zinc-ion battery system of MgxV2O5·nH2O//ZnSO4//zinc.Electrolytes with different concentration ratios of ZnSO4 and MgSO4 are investigated.The batteries measured in the 1 M ZnSO4^-1 M MgSO4 electrolyte outplay other competitors,which deliver a high specific capacity of 374 mAh g^-1 at a current density of 100 mA g^-1 and exhibit a competitive rate performance with the reversible capacity of 175 mAh g^-1 at 5 A g^-1.This study provides a promising route to improve the performance of vanadium-based cathodes for aqueous zinc-ion batteries with electrolyte optimization in cost-effective electrolytes.展开更多
Aluminum-metal batteries show great potential as next-generation energy storage due to their abundant resources and intrinsic safety.However,the crucial limitations of metallic Al anodes,such as dendrite and corrosion...Aluminum-metal batteries show great potential as next-generation energy storage due to their abundant resources and intrinsic safety.However,the crucial limitations of metallic Al anodes,such as dendrite and corrosion problems in conventional aluminum-metal batteries,remain challenging and elusive.Here,we report a novel electrodeposition strategy to prepare an optimized 3D Al anode on carbon cloth with an uniform deposition morphology,low local current density,and mitigatory volume change.The symmetrical cells with the 3D Al anode show superior stable cycling(>450 h)and low-voltage hysteresis(~170 mV)at 0.5 mA cm^(−2).High reversibility(~99.7%)is achieved for the Al plating/stripping.The graphite||Al‐4/CC full batteries show a long lifespan of 800 cycles with 54 mAh g^(−1) capacity at a high current density of 1000 mA g^(−1),benefiting from the high capacitive-controlled distribution.This study proposes a novel strategy to design 3D Al anodes for metallic-Al-based batteries by eliminating the problems of planar Al anodes and realizing the potential applications of aluminum-graphite batteries.展开更多
To overcome warping in thin bamboo bundle veneer laminated composites(TBLC),their hydrothermal deformation characteristics were systematically investigated in this study.It was found that TBLCs accelerated the release...To overcome warping in thin bamboo bundle veneer laminated composites(TBLC),their hydrothermal deformation characteristics were systematically investigated in this study.It was found that TBLCs accelerated the release of internal stress in the thickness direction in a hydrothermal environment,which increased their warpage.TBLCs showed increased warpage in the width and diagonal directions upon increasing the temperature.The warpage of Type E increased by 155.88%and 66.67%in the width and diagonal directions,respectively,when the temperature increased from 25C to 100C.The symmetrical TBLC with cross-lay-up and odd layers displayed better hydrothermal stability.We revealed that the deformation of the TBLCs could be regulated under the synergistic effect of water and temperature.These results provide a scientific basis for improving the uniformity of bamboo bundle composite materials and for developing thin bamboo bundle fiber composite materials with designable structures and controllable performance.展开更多
With the rise of aqueous multivalent rechargeable batteries,inorganic-organic hybrid cathodes have attracted more and more attention due to the complement of each other’s advantages.Herein,a strategy of designing hyb...With the rise of aqueous multivalent rechargeable batteries,inorganic-organic hybrid cathodes have attracted more and more attention due to the complement of each other’s advantages.Herein,a strategy of designing hybrid cathode is adopted for high efficient aqueous zinc-ion batteries(AZIBs).Methylene blue(MB)intercalated vanadium oxide(HVO-MB)was synthesized through sol-gel and ion exchange method.Compared with other organic-inorganic intercalation cathode,not only can the MB intercalation enlarge the HVO interlayer spacing to improve ion mobility,but also provide coordination reactions with the Zn^(2+)to enhance the intrinsic electrochemical reaction kinetics of the hybrid electrode.As a key component for the cathode of AZIBs,HVO-MB contributes a specific capacity of 418 mA h g^(-1) at 0.1 A g^(-1),high rate capability(243 mA h g^(-1) at 5 A g^(-1))and extraordinary stability(88%of capacity retention after 2000cycles at a high current density of 5 A g^(-1))in 3 M Zn(CF_(3)SO_(3))_(2) aqueous electrolyte.The electrochemical kinetics reveals HVO-MB characterized with large pseudocapacitance charge storage behavior due to the fast ion migration provided by the coordination reaction and expanded interlayer distance.Furthermore,a mixed energy storage mechanism involving Zn^(2+)insertion and coordination reaction is confirmed by various ex-situ characterization.Thus,this work opens up a new path for constructing the high performance cathode of AZIBs through organic-inorganic hybridization.展开更多
Elementary units“bamboo bundle”and“bamboo sliver”were processed and cross-linked as“bamboo-bundle veneer(BBV)”and“bamboo-sliver veneer(BSV)”for preparation of laminated composites.The concept of“high-content-...Elementary units“bamboo bundle”and“bamboo sliver”were processed and cross-linked as“bamboo-bundle veneer(BBV)”and“bamboo-sliver veneer(BSV)”for preparation of laminated composites.The concept of“high-content-adhesive surface treatment”was raised to improve boards’performance,rather than increasing adhesive absorption of every layer’s porous unit.That is,some BBVs experienced an extra“dipping&drying”to absorb more resin(named“HBBV”).The effect of the amount of knitting threads was also discussed for influencing BBV’s quality.Results indicated that light transmittance of BBVs decreased as the amount of threads added from 3 to 8,while mechanical stiffness increased.Adding two skin layers of HBBVs symmetrically was helpful to enhance 24-hour underwater and 28-hour“boil-dry-boil”dimensional stability for boards with BSVs as core,while more than two pairs of HBBVs were needed to improve 28-hour“boil-dry-boil”dimensional stability of boards with BBVs as core.Two symmetrical surface layers of BBVs/HBBVs provided BSV-boards/BBV-boards with greater bending resistance,while such“surface treatment”would not raise shearing strength of BSV-boards upon 28-hour“boil-dry-boil”treatment.Besides,the data obtained from drop-hammer impact test indicated that more than two pair of surface BBVs or HBBVs were required for significant improvement in anti-impact property.展开更多
China has rich lignite reserves which are the proper resources to be liquefied. As its low coalification degree, much hydrogen is wasted. Solvent extraction can save hydrogen and improve its liquefaction performance. ...China has rich lignite reserves which are the proper resources to be liquefied. As its low coalification degree, much hydrogen is wasted. Solvent extraction can save hydrogen and improve its liquefaction performance. The paper studies supercritical methanol treatment of lignite with a device at high temperature and pressure. Experiments mainly focus on the effects of temperature, pressure, catalysts and pretreatment ways on the extraction rate. Results indicate that the extraction rate increases with raising of temperature and pressure below 330 ℃,10 MPa. When temperature exceeds 330 ℃, extraction rate decreases slightly.? After swelling pretreatment in methanol for 8 h, the lignite is treated for 60 min at 330 ℃,8.2 MPa with NaOH as catalyst(1%wt).? The weight ratio of methanol/ Xilinhaote lignite is 5/1.? Under these conditions, the extraction rate can reach 22.88%.展开更多
Bamboo is a typical biological material widely growing in nature with excellent physical and mechanical properties.It is lightweight with high strength and toughness.The naturally optimized bamboo structure,which has ...Bamboo is a typical biological material widely growing in nature with excellent physical and mechanical properties.It is lightweight with high strength and toughness.The naturally optimized bamboo structure,which has inspired global material scientists and engineers for decades,is significantly important for the bionic design of novel structural materials with ultra-light,ultra-strong,or ultra-tough and comprehensive properties.Typical literature on innovative composite materials and structural members inspired by bamboo are reviewed in this paper,and the research progress and prospects in this field are expounded in three parts.First,the structural characteristics of the bamboo wall layer along the thickness and height directions are described in terms of chemical composition,gradient structure,pore structure,and hollow structure with variable cross-section.Second,this paper summarizes the research progress on new composite materials and structural components by applying bamboo’s structural features from the perspective of sustainability,designability,and customization.Finally,given the limitations of current research,the biomimetic scientific research on bamboo’s structural characteristics is prospected from the interpretation of bamboo structure,new bamboo-like materials,and structural design optimization perspectives,providing a reference for future research on biomimetic aspects of biomass.展开更多
Herein,g-C_(3)N_(4)quantum-dot-modified TiO_(2)nanofibers were fabricated and used as an efficient photocatalyst for the investigation of the influence of Cu^(2+)and the interaction mechanism between Cu^(2+)and surfac...Herein,g-C_(3)N_(4)quantum-dot-modified TiO_(2)nanofibers were fabricated and used as an efficient photocatalyst for the investigation of the influence of Cu^(2+)and the interaction mechanism between Cu^(2+)and surface defects in tetracycline degradation.Results showed that the effect of Cu^(2+)switched from promoting to inhibiting the tetracycline degradation as the amount of Cu^(2+)accumulated on the catalyst surface increased.The introduction of surface defects can prevent the inhibiting effect of Cu^(2+),resulting in the more complete degradation of tetracycline in contrast to the non-defective sample.Theoretical calculations further revealed that the defects can be used to tune the conduction band of the composite,inducing the reduction reaction of Cu^(2+)and inhibiting the accumulation of Cu on the surface of catalysts.Moreover,the Cu introduced to the catalyst surface provided new active sites,thereby promoting photocatalytic degradation.These findings provide new insights into the design of advanced fiber materials for water purification in complex environments.展开更多
A hierarchically 3D structured milled lamellar MoS2/nano-siIicon@carbon hybrid with medium capacity and long-term lifespan is designed by a green and scalable approach using ball milling process and spraydrying/ pyrol...A hierarchically 3D structured milled lamellar MoS2/nano-siIicon@carbon hybrid with medium capacity and long-term lifespan is designed by a green and scalable approach using ball milling process and spraydrying/ pyrolysis routes. The microspheres consist of low-content nano-silicon (20 wt%), milled lamellar M0S2 sheets and porous carbon skeletons. A mixture of silicon nanoparticles and M0S2 flakes serves as an inner core, while porous carbon pyrolyzed from petroleum pitch acts as a protective shell. The particular architecture affords robust mechanical support, abundant buffering space and enhanced electrical conductivity, thus effectively accommodating drastic volume variation during repetitive Li+ intercalation/ extraction. The Si/MoS2@C hybrid delivers a high initial discharge specific capacity of 1257.8 mA hg^-1 and exhibits a reversible capacity of 767.52 m A hg^-1 at a current density 100 mA g'1 after 250 cycles. Most impressively, the electrode depicts a superior long-cycling durability with a discharge capacity of 537.6 mA hg^-1 even after 1200 cycles at a current density of 500 m A g^-1. Meanwhile, the hybrid also shows excellent rate performance such as 388.1 mA h g^-1 even at a large current density of 3000 mA g^-1.展开更多
Structural reconstruction of nanomaterials offers a fantastic way to regulate the electronic structure of active sites and promote their catalytic activities.However,how to properly facilitate surface reconstruction t...Structural reconstruction of nanomaterials offers a fantastic way to regulate the electronic structure of active sites and promote their catalytic activities.However,how to properly facilitate surface reconstruction to overcome large overpotential that stimulate the surface reconstruction has remained elusive.Herein,we adopt a facile approach to activate surface reconstruction on Ni(OH)_(2) by incorporating F anions to achieve electro-derived structural oxidation process and further boost its oxygen evolution reaction(OER)activity.Ex situ Raman and X-ray photoemission spectroscopy studies indicate that F ions incorporation facilitated surface reconstruction and promotes the original Ni(OH)_(2)transformed into a mesoporous and amorphous F-NiOOH layer during the electrochemical process.Density functional theory(DFT)calculation reveals that this self-reconstructed NiOOH induces a space-charge effect on the p-n junction interface,which not only promotes the absorption of intermediates species(^(*)OH,^(*)O,and^(*)OOH)and charge-transfer process during catalysis,but also leads to a strong interaction of the p-n junction interface to stabilize the materials.This work opens up a new possibility to regulate the electronic structure of active sites and promote their catalytic activities.展开更多
A derivative of fluorescein,fluorescein O,O-diacrylate(FODA),was utilized in a triplet-triplet annihilation upconversion(TTA-UC)system to develop a composite ratiometric chemosensor capable of detecting cysteine(Cys)....A derivative of fluorescein,fluorescein O,O-diacrylate(FODA),was utilized in a triplet-triplet annihilation upconversion(TTA-UC)system to develop a composite ratiometric chemosensor capable of detecting cysteine(Cys).FODA acted as both the probe for Cys and the energy acceptor for upconversion(UC)emission,thereby making UC a responsive signal to Cys.In addition,the phosphorescence signal of the sensitizer in the TTA-UC system remained constant and did not respond to Cys,making it an ideal internal reference signal for constructing a ratiometric sensor.Through this simple strategy,traditional fluorescent probes can be combined with TTA-UC system to establish a ratiometric sensing platform,which can be applied in more scenarios due to the longer wavelength excitation.展开更多
基金support of this research by the National Natural Science Foundation of China(Grant No.51909165,42177438)the Start-up Research Funding of Southwest Jiaotong University(YH1100312372222)+4 种基金the Fundamental Research Funds for the Central Universities(XJ2022003201)Science and Technology Program of Guangzhou(2019050001)National Key Research and Development Program of China(2019YFE0198000)the High-End Foreign Experts Project(G2021030016L)Pearl River Talent Program(2019QN01L951)
文摘Defect engineering can give birth to novel properties for adsorption and photocatalysis in the control of antibiotics and heavy metal combined pollution with photocatalytic composites.However,the role of defects and the process mechanism are complicated and indefinable.Herein,TiO_(2)/CN/3DC was fabricated and defects were introduced into the tripartite structure with separate O_(2)plasma treatment for the single component.We find that defect engineering can improve the photocatalytic activity,attributing to the increase of the contribution from h^(+)and OH.In contrast to TiO_(2)/CN/3DC with a photocatalytic tetracycline removal rate of 75.2%,the removal rate of TC with D-TiO_(2)/CN/3DC has increased to 88.5%.Moreover,the reactive sites of tetracycline can be increased by adsorbing on the defective composites.The defect construction on TiO_(2)shows the advantages in tetracycline degradation and Cu^(2+)adsorption,but also suffers significant inhibition for the tetracycline degradation in a tetracycline/Cu^(2+)combined system.In contrast,the defect construction on graphene can achieve the cooperative removal of tetracycline and Cu^(2+).These findings can provide new insights into water treatment strategies with defect engineering.
基金the National Natural Science Foundation of China(Grant Nos.51602200,61874074)Science and Technology Project of Shenzhen(JCYJ20170817101100705)the(Key)Project of Department of Education of Guangdong Province(Grant No.2016KZDXM008).Y.Z.thanks the support from Science and Technology Project of Shenzhen(ZDSYS201707271014468).L.S.thanks the support from Shenzhen Science and Technology Project Program(JCYJ20170817094552356).
文摘MgSO4 is chosen as an additive to address the capacity fading issue in the rechargeable zinc-ion battery system of MgxV2O5·nH2O//ZnSO4//zinc.Electrolytes with different concentration ratios of ZnSO4 and MgSO4 are investigated.The batteries measured in the 1 M ZnSO4^-1 M MgSO4 electrolyte outplay other competitors,which deliver a high specific capacity of 374 mAh g^-1 at a current density of 100 mA g^-1 and exhibit a competitive rate performance with the reversible capacity of 175 mAh g^-1 at 5 A g^-1.This study provides a promising route to improve the performance of vanadium-based cathodes for aqueous zinc-ion batteries with electrolyte optimization in cost-effective electrolytes.
基金This study was funded by the Science and Technology Development Fund,Macao SAR(File no.0191/2017/A3,0041/2019/A1,0046/2019/AFJ,0021/2019/AIR)the University of Macao(File no.MYRG2017-00216-FST and MYRG2018-00192-IAPME)+2 种基金the UEA funding,Science and Technology Program of Guangzhou(2019050001)the National Key Research and Development Program of China(2019YFE0198000)Fuming Chen acknowledges the Pearl River Talent Program(2019QN01L951).
文摘Aluminum-metal batteries show great potential as next-generation energy storage due to their abundant resources and intrinsic safety.However,the crucial limitations of metallic Al anodes,such as dendrite and corrosion problems in conventional aluminum-metal batteries,remain challenging and elusive.Here,we report a novel electrodeposition strategy to prepare an optimized 3D Al anode on carbon cloth with an uniform deposition morphology,low local current density,and mitigatory volume change.The symmetrical cells with the 3D Al anode show superior stable cycling(>450 h)and low-voltage hysteresis(~170 mV)at 0.5 mA cm^(−2).High reversibility(~99.7%)is achieved for the Al plating/stripping.The graphite||Al‐4/CC full batteries show a long lifespan of 800 cycles with 54 mAh g^(−1) capacity at a high current density of 1000 mA g^(−1),benefiting from the high capacitive-controlled distribution.This study proposes a novel strategy to design 3D Al anodes for metallic-Al-based batteries by eliminating the problems of planar Al anodes and realizing the potential applications of aluminum-graphite batteries.
基金supported by the Youth Top-notch Talent Program of Science and Technology Innovation for Forestry and Grassland(2019132606).
文摘To overcome warping in thin bamboo bundle veneer laminated composites(TBLC),their hydrothermal deformation characteristics were systematically investigated in this study.It was found that TBLCs accelerated the release of internal stress in the thickness direction in a hydrothermal environment,which increased their warpage.TBLCs showed increased warpage in the width and diagonal directions upon increasing the temperature.The warpage of Type E increased by 155.88%and 66.67%in the width and diagonal directions,respectively,when the temperature increased from 25C to 100C.The symmetrical TBLC with cross-lay-up and odd layers displayed better hydrothermal stability.We revealed that the deformation of the TBLCs could be regulated under the synergistic effect of water and temperature.These results provide a scientific basis for improving the uniformity of bamboo bundle composite materials and for developing thin bamboo bundle fiber composite materials with designable structures and controllable performance.
基金supported by the National Natural Science Foundation of China(21965027 and 22065030)the Natural Science Foundation of Ningxia Province(2022AAC03109)the National First-rate Discipline Construction Project of Ningxia:Chemical Engineering and Technology(NXY-LXK2017A04)。
文摘With the rise of aqueous multivalent rechargeable batteries,inorganic-organic hybrid cathodes have attracted more and more attention due to the complement of each other’s advantages.Herein,a strategy of designing hybrid cathode is adopted for high efficient aqueous zinc-ion batteries(AZIBs).Methylene blue(MB)intercalated vanadium oxide(HVO-MB)was synthesized through sol-gel and ion exchange method.Compared with other organic-inorganic intercalation cathode,not only can the MB intercalation enlarge the HVO interlayer spacing to improve ion mobility,but also provide coordination reactions with the Zn^(2+)to enhance the intrinsic electrochemical reaction kinetics of the hybrid electrode.As a key component for the cathode of AZIBs,HVO-MB contributes a specific capacity of 418 mA h g^(-1) at 0.1 A g^(-1),high rate capability(243 mA h g^(-1) at 5 A g^(-1))and extraordinary stability(88%of capacity retention after 2000cycles at a high current density of 5 A g^(-1))in 3 M Zn(CF_(3)SO_(3))_(2) aqueous electrolyte.The electrochemical kinetics reveals HVO-MB characterized with large pseudocapacitance charge storage behavior due to the fast ion migration provided by the coordination reaction and expanded interlayer distance.Furthermore,a mixed energy storage mechanism involving Zn^(2+)insertion and coordination reaction is confirmed by various ex-situ characterization.Thus,this work opens up a new path for constructing the high performance cathode of AZIBs through organic-inorganic hybridization.
基金This work was supported by Open Fund of Key Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo&Rattan Science and Technology[ICBR-2020-11]China Postdoctoral Science Foundation[2019M660500]Fundamental Research Funds of International Center for Bamboo and Rattan[1632019003].
文摘Elementary units“bamboo bundle”and“bamboo sliver”were processed and cross-linked as“bamboo-bundle veneer(BBV)”and“bamboo-sliver veneer(BSV)”for preparation of laminated composites.The concept of“high-content-adhesive surface treatment”was raised to improve boards’performance,rather than increasing adhesive absorption of every layer’s porous unit.That is,some BBVs experienced an extra“dipping&drying”to absorb more resin(named“HBBV”).The effect of the amount of knitting threads was also discussed for influencing BBV’s quality.Results indicated that light transmittance of BBVs decreased as the amount of threads added from 3 to 8,while mechanical stiffness increased.Adding two skin layers of HBBVs symmetrically was helpful to enhance 24-hour underwater and 28-hour“boil-dry-boil”dimensional stability for boards with BSVs as core,while more than two pairs of HBBVs were needed to improve 28-hour“boil-dry-boil”dimensional stability of boards with BBVs as core.Two symmetrical surface layers of BBVs/HBBVs provided BSV-boards/BBV-boards with greater bending resistance,while such“surface treatment”would not raise shearing strength of BSV-boards upon 28-hour“boil-dry-boil”treatment.Besides,the data obtained from drop-hammer impact test indicated that more than two pair of surface BBVs or HBBVs were required for significant improvement in anti-impact property.
文摘China has rich lignite reserves which are the proper resources to be liquefied. As its low coalification degree, much hydrogen is wasted. Solvent extraction can save hydrogen and improve its liquefaction performance. The paper studies supercritical methanol treatment of lignite with a device at high temperature and pressure. Experiments mainly focus on the effects of temperature, pressure, catalysts and pretreatment ways on the extraction rate. Results indicate that the extraction rate increases with raising of temperature and pressure below 330 ℃,10 MPa. When temperature exceeds 330 ℃, extraction rate decreases slightly.? After swelling pretreatment in methanol for 8 h, the lignite is treated for 60 min at 330 ℃,8.2 MPa with NaOH as catalyst(1%wt).? The weight ratio of methanol/ Xilinhaote lignite is 5/1.? Under these conditions, the extraction rate can reach 22.88%.
文摘Bamboo is a typical biological material widely growing in nature with excellent physical and mechanical properties.It is lightweight with high strength and toughness.The naturally optimized bamboo structure,which has inspired global material scientists and engineers for decades,is significantly important for the bionic design of novel structural materials with ultra-light,ultra-strong,or ultra-tough and comprehensive properties.Typical literature on innovative composite materials and structural members inspired by bamboo are reviewed in this paper,and the research progress and prospects in this field are expounded in three parts.First,the structural characteristics of the bamboo wall layer along the thickness and height directions are described in terms of chemical composition,gradient structure,pore structure,and hollow structure with variable cross-section.Second,this paper summarizes the research progress on new composite materials and structural components by applying bamboo’s structural features from the perspective of sustainability,designability,and customization.Finally,given the limitations of current research,the biomimetic scientific research on bamboo’s structural characteristics is prospected from the interpretation of bamboo structure,new bamboo-like materials,and structural design optimization perspectives,providing a reference for future research on biomimetic aspects of biomass.
基金support of this research by the National Natural Science Foundation of China(Grant nos.51909165,42177438)China Postdoctoral Science Foundation(2020TQ0109,2020M682753).Science and Technology Program of Guangzhou(2019050001)+1 种基金National Key Research and Development Program of China(2019YFE0198000)F.Chen acknowledges the Pearl River Talent Program(2019QN01L951).
文摘Herein,g-C_(3)N_(4)quantum-dot-modified TiO_(2)nanofibers were fabricated and used as an efficient photocatalyst for the investigation of the influence of Cu^(2+)and the interaction mechanism between Cu^(2+)and surface defects in tetracycline degradation.Results showed that the effect of Cu^(2+)switched from promoting to inhibiting the tetracycline degradation as the amount of Cu^(2+)accumulated on the catalyst surface increased.The introduction of surface defects can prevent the inhibiting effect of Cu^(2+),resulting in the more complete degradation of tetracycline in contrast to the non-defective sample.Theoretical calculations further revealed that the defects can be used to tune the conduction band of the composite,inducing the reduction reaction of Cu^(2+)and inhibiting the accumulation of Cu on the surface of catalysts.Moreover,the Cu introduced to the catalyst surface provided new active sites,thereby promoting photocatalytic degradation.These findings provide new insights into the design of advanced fiber materials for water purification in complex environments.
基金support of the Outstanding Young Scholar Project (8S0256) from South China Normal Universitythe Union Project of the National Natural Science Foundation of China and Guangdong Province (U1601214)+2 种基金the Scientific and Technological Plan of Guangdong Province (2017A040405047)the Key Projects of Guangdong Province Nature Science Foundation (2017B030311013)the Scientific and Technological Plan of Guangzhou City (201607010274)
文摘A hierarchically 3D structured milled lamellar MoS2/nano-siIicon@carbon hybrid with medium capacity and long-term lifespan is designed by a green and scalable approach using ball milling process and spraydrying/ pyrolysis routes. The microspheres consist of low-content nano-silicon (20 wt%), milled lamellar M0S2 sheets and porous carbon skeletons. A mixture of silicon nanoparticles and M0S2 flakes serves as an inner core, while porous carbon pyrolyzed from petroleum pitch acts as a protective shell. The particular architecture affords robust mechanical support, abundant buffering space and enhanced electrical conductivity, thus effectively accommodating drastic volume variation during repetitive Li+ intercalation/ extraction. The Si/MoS2@C hybrid delivers a high initial discharge specific capacity of 1257.8 mA hg^-1 and exhibits a reversible capacity of 767.52 m A hg^-1 at a current density 100 mA g'1 after 250 cycles. Most impressively, the electrode depicts a superior long-cycling durability with a discharge capacity of 537.6 mA hg^-1 even after 1200 cycles at a current density of 500 m A g^-1. Meanwhile, the hybrid also shows excellent rate performance such as 388.1 mA h g^-1 even at a large current density of 3000 mA g^-1.
基金This work was funded by the Science and Technology Development Fund,Macao SAR(Nos.0191/2017/A3,0041/2019/A1,0046/2019/AFJ,and 0021/2019/AIR)University of Macao(Nos.MYRG2017-00216-FST and MYRG2018-00192-IAPME)+3 种基金UEA funding,the National Natural Science Foundation of China(Nos.51773211 and 21961160700)the Beijing Municipal Science&Technology Commission,the IBS(IBS-R019-D1)the State Key Laboratory of Organic-Inorganic Composites(OIC)(No.202101002)The DFT calculations were performed at High Performance Computing Cluster(HPCC)of Information and Communication Technology Office(ICTO)at University of Macao.
文摘Structural reconstruction of nanomaterials offers a fantastic way to regulate the electronic structure of active sites and promote their catalytic activities.However,how to properly facilitate surface reconstruction to overcome large overpotential that stimulate the surface reconstruction has remained elusive.Herein,we adopt a facile approach to activate surface reconstruction on Ni(OH)_(2) by incorporating F anions to achieve electro-derived structural oxidation process and further boost its oxygen evolution reaction(OER)activity.Ex situ Raman and X-ray photoemission spectroscopy studies indicate that F ions incorporation facilitated surface reconstruction and promotes the original Ni(OH)_(2)transformed into a mesoporous and amorphous F-NiOOH layer during the electrochemical process.Density functional theory(DFT)calculation reveals that this self-reconstructed NiOOH induces a space-charge effect on the p-n junction interface,which not only promotes the absorption of intermediates species(^(*)OH,^(*)O,and^(*)OOH)and charge-transfer process during catalysis,but also leads to a strong interaction of the p-n junction interface to stabilize the materials.This work opens up a new possibility to regulate the electronic structure of active sites and promote their catalytic activities.
基金financially supported by National Natural Science Foundation of China(51873145)Qing Lan Project+1 种基金333 High-level Talents Training Project of Jiangsu Province(BRA2018340)Six Talent Summits Project of Jiangsu Province(XCL-79)
文摘A derivative of fluorescein,fluorescein O,O-diacrylate(FODA),was utilized in a triplet-triplet annihilation upconversion(TTA-UC)system to develop a composite ratiometric chemosensor capable of detecting cysteine(Cys).FODA acted as both the probe for Cys and the energy acceptor for upconversion(UC)emission,thereby making UC a responsive signal to Cys.In addition,the phosphorescence signal of the sensitizer in the TTA-UC system remained constant and did not respond to Cys,making it an ideal internal reference signal for constructing a ratiometric sensor.Through this simple strategy,traditional fluorescent probes can be combined with TTA-UC system to establish a ratiometric sensing platform,which can be applied in more scenarios due to the longer wavelength excitation.