The Proccss of gascous hydrogcn charging into a Ti_3Al- based alloy in the temperature range of 500-650℃isinvcstigatcd. The rcsnlls snoxvc that in rclatiollshil, between the average hydrogen concentration at constant...The Proccss of gascous hydrogcn charging into a Ti_3Al- based alloy in the temperature range of 500-650℃isinvcstigatcd. The rcsnlls snoxvc that in rclatiollshil, between the average hydrogen concentration at constant tempreature and charging time reveals a parabolie rate law Applying the theory of lattice constant tcnlpcralurc and hrgillg tin rcvcals a parabolic riltc laiv. Applyillg tbcthcoly oftatticc dillbsio to allalyzc the hydrogcll diethesioll they andthat cncrgy of hydrogcn diffusion is 90.40 kJ/mol. and the equilibrium hydrogen content in the alloy depends on the temperature of the gaseous hydrogen charging process展开更多
The hot corrosion behaviour of a modified Ti3Al-based alloy under thin Na2SO4deposit film was investigated at910and950°C in air.The corrosion product was identified by XRD and its morphologies on the surface and ...The hot corrosion behaviour of a modified Ti3Al-based alloy under thin Na2SO4deposit film was investigated at910and950°C in air.The corrosion product was identified by XRD and its morphologies on the surface and cross-section were observed bySEM.The alloy suffered from considerable hot corrosion attack.The mass gain versus time curves obtained by TGA exhibited tworegions of different kinetics.The whole corroded layer consisted of loose and porous mixture oxides of TiO2,Nb2O5and Al2O3.Numerous small nodules of corrosion product were observed.An illustrative schematic was established to describe the formationprocess of such nodules.It seemed that the refractory oxides played a significantly important role in determining the development ofhot corrosion attack.展开更多
Supercapacitors are indispensable for next-generation energy storage,achieving high energy density and long-term durability remains a formidable challenge.Conventional CoS suffers from poor conductivity,while Ti_(3)C_...Supercapacitors are indispensable for next-generation energy storage,achieving high energy density and long-term durability remains a formidable challenge.Conventional CoS suffers from poor conductivity,while Ti_(3)C_(2)faces severe restacking.Herein,we report a novel synthesis strategy that integrates metal-organic framework(MOF)growth with electrostatic self-assembly to construct heterojunction of CoS nanotubes coated with ultrathin Ti_(3)C_(2)nanofilms.Material characterization via SEM,TEM,XRD,and XPS systematically confirms the heterostructure formation,and chemical composition.This rational design synergistically leverages CoS high pseudocapacitance and Ti_(3)C_(2)metallic conductivity while the heterostructure mitigates restacking,enhances charge transfer,and stabilizes interfacial interactions.Density functional theory(DFT)calculations reveal strengthened OH-adsorption at the Co-Ti interface(E_(ad)=1.106 eV).Consequently,the CoS/Ti_(3)C_(2)@CC delivers a remarkable specific capacitance of 1034.21 F g^(-1) at 1 A g^(-1).Assembled into a supercapacitor,CoS/Ti_(3)C_(2)@CC//AC achieves a high energy density of 74.22 Wh kg^(-1) at 800 W kg^(-1),maintaining 89.13%initial capacitance after 10,000 cycles.Significantly,it exhibits a remarkably low leakage current(0.23μA)and ultra-prolonged voltage retention(47.14%after 120 h),underscoring exceptional durability.This work pioneers a rational heterostructure engineering strategy by integrating MOF-derived architectures with conductive MXene nanofilms,offering critical insights for the development of ultra-durable supercapacitors.展开更多
The limited redox capability of photocatalysts often leads to harmful NO_(2) byproduct formation during photocatalytic NO oxidation.Herein,Bi_(4)Ti_(3)O_(12) nanosheets modified with plasmonic metallic bismuth and abu...The limited redox capability of photocatalysts often leads to harmful NO_(2) byproduct formation during photocatalytic NO oxidation.Herein,Bi_(4)Ti_(3)O_(12) nanosheets modified with plasmonic metallic bismuth and abundant oxygen vacancies were synthesized via an in-situ reduction method.The optimized catalyst(BTOR2,with a molar ratio of 40%NaBH_(4) to Bi_(4)Ti_(3)O_(12))achieved a maximum NO removal efficiency of 62.3%,significantly higher than pristine Bi_(4)Ti_(3)O_(12)(40.5%) while minimizing NO_(2) production.The results reveal that the synergistic effects of Bi’s plasmonic resonance and oxygen vacancies enhanced visible light absorption and charge separation.The density functional theory(DFT)analysis showed electrons can transfer from Bi_(4)Ti_(3)O_(12)to Bi,promoting O_(2)activation to·O_(2)^(-)radicals.In-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)confirmed that light-induced H2O adsorption was strengthened,improving·OH radical generation.These radicals promoted the selective conversion of activated NO^(-) to NO_(3)^(-),rather than NO_(2).This work provides valuable insights for advancing research into efficient photocatalysts for air pollution control.展开更多
2D MXenes,particularly Ti_(3)C_(2)T_(x),have emerged as promising multifu nctional materials for advancing solidstate batteries(SSBs).While SSBs offer superior safety and energy density over liquid-electrolyte systems...2D MXenes,particularly Ti_(3)C_(2)T_(x),have emerged as promising multifu nctional materials for advancing solidstate batteries(SSBs).While SSBs offer superior safety and energy density over liquid-electrolyte systems,critical challenges such as interfacial resistance,limited ion transport,dendrite growth,and mechanical degradation hinder their widespread adoption.This review aims to provide a comprehensive analysis of the roles and fu nctions of Ti_(3)C_(2)T_(x) MXenes in SSBs,emphasizing their application as interlayers,anode/cathode additives,and current collectors,and highlighting their impact on interracial stability,ionic/electro nic transport,electrochemical performance,and cycling durability in SSB architectures.Unlike other 2D materials,Ti_(3)C_(2)T_(x) exhibits outsta nding metallic conductivity,tu nable surface terminations,hydrophilicity,and excellent mechanical flexibility,making it ideal for multifu nctional integration in SSBs,As a component in solid-state electrolytes(SSEs),Ti_(3)C_(2)T_(x) improves ionic conductivity and mecha nical strength.When used in electrodes,it serves as a conductive scaffold that enhances charge transport and structural durability.Additionally,its role as an interfacial interlayer effectively reduces interfacial impedance,accommodates volume changes,and suppresses dendrite formation.Its lightweight and high conductivity enable its use as a current collector.This review highlights recent advances in Ti_(3)C_(2)T_(x)-based components for SSBs like Li-,Na-,Zn,Li-S,etc.,emphasizing enha ncements in ion/electron transport,interfacial stability,and structural robustness.Finally,the review outlines challenges and opportunities along with a future outlook focused on improving the MXene oxidation,tailoring surface terminations,improving long-term stability,and exploring scalable fabrication strategies for MXene-based SSB components.展开更多
文摘The Proccss of gascous hydrogcn charging into a Ti_3Al- based alloy in the temperature range of 500-650℃isinvcstigatcd. The rcsnlls snoxvc that in rclatiollshil, between the average hydrogen concentration at constant tempreature and charging time reveals a parabolie rate law Applying the theory of lattice constant tcnlpcralurc and hrgillg tin rcvcals a parabolic riltc laiv. Applyillg tbcthcoly oftatticc dillbsio to allalyzc the hydrogcll diethesioll they andthat cncrgy of hydrogcn diffusion is 90.40 kJ/mol. and the equilibrium hydrogen content in the alloy depends on the temperature of the gaseous hydrogen charging process
基金Projects(51271191,51571205)supported by the National Natural Science Foundation of China
文摘The hot corrosion behaviour of a modified Ti3Al-based alloy under thin Na2SO4deposit film was investigated at910and950°C in air.The corrosion product was identified by XRD and its morphologies on the surface and cross-section were observed bySEM.The alloy suffered from considerable hot corrosion attack.The mass gain versus time curves obtained by TGA exhibited tworegions of different kinetics.The whole corroded layer consisted of loose and porous mixture oxides of TiO2,Nb2O5and Al2O3.Numerous small nodules of corrosion product were observed.An illustrative schematic was established to describe the formationprocess of such nodules.It seemed that the refractory oxides played a significantly important role in determining the development ofhot corrosion attack.
基金supported by the National Natural Science Foundation of China(22201107,52203147)Zhejiang Provincial Natural Science Foundation of China(MS25B040011)significant science and technology projects of LongMen Laboratory in Henan Province(231100220100).
文摘Supercapacitors are indispensable for next-generation energy storage,achieving high energy density and long-term durability remains a formidable challenge.Conventional CoS suffers from poor conductivity,while Ti_(3)C_(2)faces severe restacking.Herein,we report a novel synthesis strategy that integrates metal-organic framework(MOF)growth with electrostatic self-assembly to construct heterojunction of CoS nanotubes coated with ultrathin Ti_(3)C_(2)nanofilms.Material characterization via SEM,TEM,XRD,and XPS systematically confirms the heterostructure formation,and chemical composition.This rational design synergistically leverages CoS high pseudocapacitance and Ti_(3)C_(2)metallic conductivity while the heterostructure mitigates restacking,enhances charge transfer,and stabilizes interfacial interactions.Density functional theory(DFT)calculations reveal strengthened OH-adsorption at the Co-Ti interface(E_(ad)=1.106 eV).Consequently,the CoS/Ti_(3)C_(2)@CC delivers a remarkable specific capacitance of 1034.21 F g^(-1) at 1 A g^(-1).Assembled into a supercapacitor,CoS/Ti_(3)C_(2)@CC//AC achieves a high energy density of 74.22 Wh kg^(-1) at 800 W kg^(-1),maintaining 89.13%initial capacitance after 10,000 cycles.Significantly,it exhibits a remarkably low leakage current(0.23μA)and ultra-prolonged voltage retention(47.14%after 120 h),underscoring exceptional durability.This work pioneers a rational heterostructure engineering strategy by integrating MOF-derived architectures with conductive MXene nanofilms,offering critical insights for the development of ultra-durable supercapacitors.
基金supported by the Natural Science Foundation of Chongqing(Nos.CSTB2024NSCQ-MSX1278,CSTB2023NSCQ-MSX0006)Technology Innovation Project of Shapingba District,Chongqing(No.2024004)+2 种基金Science and Technology Research Program of Chongqing Municipal Education Commission(Nos.KJZD-K202403102,KJQN202103110,KJQN202400512,KJQN202403107)National Natural Science Foundation of China(No.22406014)China Postdoctoral Science Foundation(No.2023MD744137).
文摘The limited redox capability of photocatalysts often leads to harmful NO_(2) byproduct formation during photocatalytic NO oxidation.Herein,Bi_(4)Ti_(3)O_(12) nanosheets modified with plasmonic metallic bismuth and abundant oxygen vacancies were synthesized via an in-situ reduction method.The optimized catalyst(BTOR2,with a molar ratio of 40%NaBH_(4) to Bi_(4)Ti_(3)O_(12))achieved a maximum NO removal efficiency of 62.3%,significantly higher than pristine Bi_(4)Ti_(3)O_(12)(40.5%) while minimizing NO_(2) production.The results reveal that the synergistic effects of Bi’s plasmonic resonance and oxygen vacancies enhanced visible light absorption and charge separation.The density functional theory(DFT)analysis showed electrons can transfer from Bi_(4)Ti_(3)O_(12)to Bi,promoting O_(2)activation to·O_(2)^(-)radicals.In-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)confirmed that light-induced H2O adsorption was strengthened,improving·OH radical generation.These radicals promoted the selective conversion of activated NO^(-) to NO_(3)^(-),rather than NO_(2).This work provides valuable insights for advancing research into efficient photocatalysts for air pollution control.
基金supported by a National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(NRF-2020R1A6A1A03043435 and 2020R1A2C1099862)supported by the Korea Institute for Advancement of Technology(KIAT)grant funded by the Korean Government(MOTIE)(P0012451,The Competency Development Program for Industry Specialist)。
文摘2D MXenes,particularly Ti_(3)C_(2)T_(x),have emerged as promising multifu nctional materials for advancing solidstate batteries(SSBs).While SSBs offer superior safety and energy density over liquid-electrolyte systems,critical challenges such as interfacial resistance,limited ion transport,dendrite growth,and mechanical degradation hinder their widespread adoption.This review aims to provide a comprehensive analysis of the roles and fu nctions of Ti_(3)C_(2)T_(x) MXenes in SSBs,emphasizing their application as interlayers,anode/cathode additives,and current collectors,and highlighting their impact on interracial stability,ionic/electro nic transport,electrochemical performance,and cycling durability in SSB architectures.Unlike other 2D materials,Ti_(3)C_(2)T_(x) exhibits outsta nding metallic conductivity,tu nable surface terminations,hydrophilicity,and excellent mechanical flexibility,making it ideal for multifu nctional integration in SSBs,As a component in solid-state electrolytes(SSEs),Ti_(3)C_(2)T_(x) improves ionic conductivity and mecha nical strength.When used in electrodes,it serves as a conductive scaffold that enhances charge transport and structural durability.Additionally,its role as an interfacial interlayer effectively reduces interfacial impedance,accommodates volume changes,and suppresses dendrite formation.Its lightweight and high conductivity enable its use as a current collector.This review highlights recent advances in Ti_(3)C_(2)T_(x)-based components for SSBs like Li-,Na-,Zn,Li-S,etc.,emphasizing enha ncements in ion/electron transport,interfacial stability,and structural robustness.Finally,the review outlines challenges and opportunities along with a future outlook focused on improving the MXene oxidation,tailoring surface terminations,improving long-term stability,and exploring scalable fabrication strategies for MXene-based SSB components.
