To overcome the serious technological issues affecting lithium-sulfur(Li-S) batteries,such as sluggish sulfur redox kinetics and the detrimental shuttle effect,heterostructure engineering has been investigated as a st...To overcome the serious technological issues affecting lithium-sulfur(Li-S) batteries,such as sluggish sulfur redox kinetics and the detrimental shuttle effect,heterostructure engineering has been investigated as a strategy to effectively capture soluble lithium polysulfide intermediates and promote their conversion reaction by integrating highly polar metal oxides with catalytically active metals sulfides.However,to fully exploit the outstanding properties of heterostructure-based composites,their detailed structure and interfacial contacts should be designed rationally.Herein,optimally arranged TiO_(2)and MoS_(2)-based heterostructures(TiO_(2)@MoS_(2)) are fabricated on carbon cloth as a multifunctional interlayer to efficiently trap polysulfide intermediates and accelerate their redox kinetics.Owing to the synergistic effects between TiO_(2)and MoS_(2)and the uniform heterointerface distribution that induces the ideally oriented built-in electric field,Li-S batteries with TiO_(2)@MoS_(2)interlayers exhibit high rate capability(601 mA h g^(-1)at 5 C),good cycling stability(capacity-fade rate of 0.067% per cycle over 500 cycles at2 C),and satisfactory areal capacity(5.2 mA h cm^(-2)) under an increased sulfur loading of 5.2 mg cm^(-2).Moreover,by comparing with a MoS_(2)@TiO_(2)interlayer composed of reversely arranged heterostructures,the effect of the built-in electric field’s direction on the electrocatalytic reactions of polysulfide intermediates is thoroughly investigated for the first time.The superior electrocatalytic activities of the rationally arranged TiO_(2)@MoS_(2)interlayer demonstrate the importance of optimizing the built-in electric field of heterostructures for producing high-performance Li-S batteries.展开更多
Li-argyrodites are promising solid electrolytes(SEs)for solid-state Li-ion batteries(SSLBs),but their large-scale industrial application remains a challenge.Conventional synthesis methods for SEs suffer from long reac...Li-argyrodites are promising solid electrolytes(SEs)for solid-state Li-ion batteries(SSLBs),but their large-scale industrial application remains a challenge.Conventional synthesis methods for SEs suffer from long reaction times and high energy consumption.In this study,we present a wet process for the synthesis of halogen-rich argyrodite Li_(6-a)PS_(5-a)Cl_(1+a)precursors(LPSCl_(1+a)-P,a=0–0.7)via an energysaving microwave-assisted process.Utilizing vibrational heating,we accelerate the formation of Liargyrodite precursor,even at excessive Cl-ion concentration,which significantly shortens the reaction time compared to traditional methods.After crystallization,we successfully synthesize the Liargyrodite,Li_(5.5)PS_(4.5)Cl_(1.5),which exhibits the superior ionic conductivity(7.8 mS cm^(-1))and low activation energy(0.23 eV)along with extremely low electric conductivity.The Li_(5.5)PS_(4.5)Cl_(1.5)exhibits superior Li compatibility owing to its high reversible striping/plating ability(over 5000 h)and high current density acceptability(1.3 mA cm^(-2)).It also exhibits excellent cycle reversibility and rate capability with NCM622 cathode(148.3 mA h g^(-1)at 1 C for 100 cycles with capacity retention of 85.6%).This finding suggests a potentially simpler and more scalable synthetic route to produce high-performance SEs.展开更多
基金supported by the National R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2018M3D1A1058793 and 2021R1A3B1068920)supported by the Creative Materials Discovery Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2018M3D1A1058744)the Yonsei Signature Research Cluster Program of 2021 (2021-22-0002)。
文摘To overcome the serious technological issues affecting lithium-sulfur(Li-S) batteries,such as sluggish sulfur redox kinetics and the detrimental shuttle effect,heterostructure engineering has been investigated as a strategy to effectively capture soluble lithium polysulfide intermediates and promote their conversion reaction by integrating highly polar metal oxides with catalytically active metals sulfides.However,to fully exploit the outstanding properties of heterostructure-based composites,their detailed structure and interfacial contacts should be designed rationally.Herein,optimally arranged TiO_(2)and MoS_(2)-based heterostructures(TiO_(2)@MoS_(2)) are fabricated on carbon cloth as a multifunctional interlayer to efficiently trap polysulfide intermediates and accelerate their redox kinetics.Owing to the synergistic effects between TiO_(2)and MoS_(2)and the uniform heterointerface distribution that induces the ideally oriented built-in electric field,Li-S batteries with TiO_(2)@MoS_(2)interlayers exhibit high rate capability(601 mA h g^(-1)at 5 C),good cycling stability(capacity-fade rate of 0.067% per cycle over 500 cycles at2 C),and satisfactory areal capacity(5.2 mA h cm^(-2)) under an increased sulfur loading of 5.2 mg cm^(-2).Moreover,by comparing with a MoS_(2)@TiO_(2)interlayer composed of reversely arranged heterostructures,the effect of the built-in electric field’s direction on the electrocatalytic reactions of polysulfide intermediates is thoroughly investigated for the first time.The superior electrocatalytic activities of the rationally arranged TiO_(2)@MoS_(2)interlayer demonstrate the importance of optimizing the built-in electric field of heterostructures for producing high-performance Li-S batteries.
基金supported by the Basic Science Research Program through National Research Foundation of Korea(NRF)grant funded by the Ministry of Science and ICT(RS-2022-NR070534)supported by the National Research Council of Science&Technology(NST)grant by the Korea government(MSIT)(2710024139)。
文摘Li-argyrodites are promising solid electrolytes(SEs)for solid-state Li-ion batteries(SSLBs),but their large-scale industrial application remains a challenge.Conventional synthesis methods for SEs suffer from long reaction times and high energy consumption.In this study,we present a wet process for the synthesis of halogen-rich argyrodite Li_(6-a)PS_(5-a)Cl_(1+a)precursors(LPSCl_(1+a)-P,a=0–0.7)via an energysaving microwave-assisted process.Utilizing vibrational heating,we accelerate the formation of Liargyrodite precursor,even at excessive Cl-ion concentration,which significantly shortens the reaction time compared to traditional methods.After crystallization,we successfully synthesize the Liargyrodite,Li_(5.5)PS_(4.5)Cl_(1.5),which exhibits the superior ionic conductivity(7.8 mS cm^(-1))and low activation energy(0.23 eV)along with extremely low electric conductivity.The Li_(5.5)PS_(4.5)Cl_(1.5)exhibits superior Li compatibility owing to its high reversible striping/plating ability(over 5000 h)and high current density acceptability(1.3 mA cm^(-2)).It also exhibits excellent cycle reversibility and rate capability with NCM622 cathode(148.3 mA h g^(-1)at 1 C for 100 cycles with capacity retention of 85.6%).This finding suggests a potentially simpler and more scalable synthetic route to produce high-performance SEs.
