Although carbon-supported platinum(Pt/C) is still considered the most active electrocatalyst for hydrogen evolution reaction(HER) and oxygen reduction reaction(ORR), its applications in metal–air batteries as a catho...Although carbon-supported platinum(Pt/C) is still considered the most active electrocatalyst for hydrogen evolution reaction(HER) and oxygen reduction reaction(ORR), its applications in metal–air batteries as a cathode catalyst, or for oxygen generation via water splitting electrolysis as an anode catalyst is mainly constrained by the insufficient kinetic activity and stability in the oxygen evolution reaction(OER). Here, MOF-253-derived nitrogen-doped carbon(N/C)-confined Pt single nanocrystals(Pt@N/C) have been synthesized and shown to be efficient catalysts for the OER. Even with low Pt mass loading of 6.1 wt%(Pt@N/C-10), the catalyst exhibits greatly improved activity and long-time stability as an efficient OER catalyst. Such high catalytic performance is attributed to the core-shell structure relationship, in which the active N-doped-C shell not only provides a protective shield to avoid rapid Pt nanocrystal oxidation at high potentials and inhibits the Pt migration and agglomeration, but also improves the conductivity and charge transfer kinetics.展开更多
MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper...MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper doping and carbon-based confinement.Residual carbon(RC),derived from acid-washed coal gasification fine slag(CGFS),serves as a conductive and porous framework for the directional growth of Cu-doped MnO_(2) nanowires(CMO@RC).The synergistic modulation of Cu-induced electronic structure tuning and carbon confinement induced mechanical/electrical stabilization significantly enhances Zn^(2+) transport and electrochemical performance.CMO@RC achieves a high capacity of 563 mA·h·g^(−1) at 0.1 A·g^(−1) and maintains 106%after 1000 cycles at 1 A·g^(−1).Kinetic analyses confirm the dual-path Zn^(2+) diffusion and accelerated reaction kinetics,while DFT calculations reveal that Cu doping enhances Mn 3d orbital hybridization and electron interaction with carbon,elevating the density of states near the Fermi level and reducing charge transfer barriers.Furthermore,pouch cell testing demonstrates outstanding flexibility and mechanical resilience.This study provides a cost-effective and scalable strategy for high-performance AZIBs,leveraging both experimental and theoretical validations.展开更多
Lithium-sulfur(Li-S)batteries have been considered as promising energy storage systems due to the merits of high energy density and low cost.However,the lithium polysulfides(LiPSs)diffusion and sluggish redox kinetics...Lithium-sulfur(Li-S)batteries have been considered as promising energy storage systems due to the merits of high energy density and low cost.However,the lithium polysulfides(LiPSs)diffusion and sluggish redox kinetics hamper the battery performance.In this work,low-bandgap indium oxide(In_(2)O_(3))with dense oxygen vacancies(In_(2)O_(3−x),0<x<3)confined in nitrogen-doped carbon column(NC)is developed as a desirable LiPSs immobilizer and promoter to address these intractable problems.The NC confined In_(2)O_(3−x)with rich O vacancies(In_(2)O_(3−x)@NC)lowers the bandgap of 1.78 eV,strengthens the chemical adsorbability to LiPSs,and catalyzes the bidirectional Li_(2)S redox.Attributed to the structural and chemical cooperativities,the obtained sulfur electrodes exhibit a stable cycling over 550 cycles at 1.0 C and splendid rate capability up to 4.0 C.More significantly,when the sulfur-loading reaches as high as 5.5 mg·cm^(−2),the cathodes achieve an areal capacity of 5.12 mAh·cm^(−2)at 0.1 C.The strategy of NC confined catalyst with rich defects engineering demonstrates great promise in the development of practical Li-S batteries.展开更多
Developing high performance electrocatalysts for the cathodic oxygen reduction reaction(ORR)is essential for the widespread application of fuel cells.Herein,a promising Pt_(2)NiCo atomic ordered ternary intermetallic ...Developing high performance electrocatalysts for the cathodic oxygen reduction reaction(ORR)is essential for the widespread application of fuel cells.Herein,a promising Pt_(2)NiCo atomic ordered ternary intermetallic compound with N-doped carbon layer coating(o-Pt_(2)NiCo@NC)has been synthesized via a facile method and applied in acidic ORR.The confinement effect provided by the carbon layer not only inhibits the agglomeration and sintering of intermetallic nanoparticles during high temperature process but also provides adequate protection for the nanoparticles,mitigating the aggregation,detachment and poisoning of nanoparticles during the electrochemical process.As a result,the o-Pt_(2)NiCo@NC demonstrates a mass activity(MA)and specific activity(SA)of 0.65 A/mgPt and 1.41mA/cm_(Pt) ^(2) in 0.1mol/L HClO_(4),respectively.In addition,after 30,000 potential cycles from 0.6 V to 1.0 V,the MA of o-Pt_(2)NiCo@NC shows much lower decrease than the disordered Pt_(2)NiCo alloy and Pt/C.Even cycling at high potential cycles of 1.5 V for 10,000 cycles,the MA still retains∼70%,demonstrating superior long-term durability.Furthermore,the o-Pt_(2)NiCo@NC also exhibits strong tolerance to CO,SO_(x),and PO_(x) molecules in toxicity tolerance tests.The strategy in this work provides a novel insight for the development of ORR catalysts with high catalytic activity,durability and toxicity tolerance.展开更多
文摘Although carbon-supported platinum(Pt/C) is still considered the most active electrocatalyst for hydrogen evolution reaction(HER) and oxygen reduction reaction(ORR), its applications in metal–air batteries as a cathode catalyst, or for oxygen generation via water splitting electrolysis as an anode catalyst is mainly constrained by the insufficient kinetic activity and stability in the oxygen evolution reaction(OER). Here, MOF-253-derived nitrogen-doped carbon(N/C)-confined Pt single nanocrystals(Pt@N/C) have been synthesized and shown to be efficient catalysts for the OER. Even with low Pt mass loading of 6.1 wt%(Pt@N/C-10), the catalyst exhibits greatly improved activity and long-time stability as an efficient OER catalyst. Such high catalytic performance is attributed to the core-shell structure relationship, in which the active N-doped-C shell not only provides a protective shield to avoid rapid Pt nanocrystal oxidation at high potentials and inhibits the Pt migration and agglomeration, but also improves the conductivity and charge transfer kinetics.
基金support from the Key projects of scientific research projects of universities in Anhui Province(2024AH050360).
文摘MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper doping and carbon-based confinement.Residual carbon(RC),derived from acid-washed coal gasification fine slag(CGFS),serves as a conductive and porous framework for the directional growth of Cu-doped MnO_(2) nanowires(CMO@RC).The synergistic modulation of Cu-induced electronic structure tuning and carbon confinement induced mechanical/electrical stabilization significantly enhances Zn^(2+) transport and electrochemical performance.CMO@RC achieves a high capacity of 563 mA·h·g^(−1) at 0.1 A·g^(−1) and maintains 106%after 1000 cycles at 1 A·g^(−1).Kinetic analyses confirm the dual-path Zn^(2+) diffusion and accelerated reaction kinetics,while DFT calculations reveal that Cu doping enhances Mn 3d orbital hybridization and electron interaction with carbon,elevating the density of states near the Fermi level and reducing charge transfer barriers.Furthermore,pouch cell testing demonstrates outstanding flexibility and mechanical resilience.This study provides a cost-effective and scalable strategy for high-performance AZIBs,leveraging both experimental and theoretical validations.
基金the National Natural Science Foundation of China(No.22279036)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003).
文摘Lithium-sulfur(Li-S)batteries have been considered as promising energy storage systems due to the merits of high energy density and low cost.However,the lithium polysulfides(LiPSs)diffusion and sluggish redox kinetics hamper the battery performance.In this work,low-bandgap indium oxide(In_(2)O_(3))with dense oxygen vacancies(In_(2)O_(3−x),0<x<3)confined in nitrogen-doped carbon column(NC)is developed as a desirable LiPSs immobilizer and promoter to address these intractable problems.The NC confined In_(2)O_(3−x)with rich O vacancies(In_(2)O_(3−x)@NC)lowers the bandgap of 1.78 eV,strengthens the chemical adsorbability to LiPSs,and catalyzes the bidirectional Li_(2)S redox.Attributed to the structural and chemical cooperativities,the obtained sulfur electrodes exhibit a stable cycling over 550 cycles at 1.0 C and splendid rate capability up to 4.0 C.More significantly,when the sulfur-loading reaches as high as 5.5 mg·cm^(−2),the cathodes achieve an areal capacity of 5.12 mAh·cm^(−2)at 0.1 C.The strategy of NC confined catalyst with rich defects engineering demonstrates great promise in the development of practical Li-S batteries.
基金supported by the National Natural Science Foundation(No.22279036)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003).
文摘Developing high performance electrocatalysts for the cathodic oxygen reduction reaction(ORR)is essential for the widespread application of fuel cells.Herein,a promising Pt_(2)NiCo atomic ordered ternary intermetallic compound with N-doped carbon layer coating(o-Pt_(2)NiCo@NC)has been synthesized via a facile method and applied in acidic ORR.The confinement effect provided by the carbon layer not only inhibits the agglomeration and sintering of intermetallic nanoparticles during high temperature process but also provides adequate protection for the nanoparticles,mitigating the aggregation,detachment and poisoning of nanoparticles during the electrochemical process.As a result,the o-Pt_(2)NiCo@NC demonstrates a mass activity(MA)and specific activity(SA)of 0.65 A/mgPt and 1.41mA/cm_(Pt) ^(2) in 0.1mol/L HClO_(4),respectively.In addition,after 30,000 potential cycles from 0.6 V to 1.0 V,the MA of o-Pt_(2)NiCo@NC shows much lower decrease than the disordered Pt_(2)NiCo alloy and Pt/C.Even cycling at high potential cycles of 1.5 V for 10,000 cycles,the MA still retains∼70%,demonstrating superior long-term durability.Furthermore,the o-Pt_(2)NiCo@NC also exhibits strong tolerance to CO,SO_(x),and PO_(x) molecules in toxicity tolerance tests.The strategy in this work provides a novel insight for the development of ORR catalysts with high catalytic activity,durability and toxicity tolerance.
