Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish ...Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox dynamics.Herein,we supply a strategy to optimize the electron structure of Ni_(2)P by concurrently introducing B-doped atoms and P vacancies in Ni_(2)P (Vp-B-Ni_(2)P),thereby enhancing the bidirectional sulfur conversion.The study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni_(2)P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides (LiPSs) as well as expediting the bidirectional conversion kinetics of sulfur species.Meanwhile,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni_(2)P selectively promotes Li2S dissolution and nucleation processes.Thus,the Li-S batteries with Vp-B-Ni_(2)P-separators present outstanding rate ability of 777 m A h g^(-1)at 5 C and high areal capacity of 8.03 mA h cm^(-2)under E/S of 5μL mg^(-1)and sulfur loading of 7.20 mg cm^(-2).This work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.展开更多
Lithium-sulfur(Li-S)batteries are considered a potential candidate for next-generation energy-dense and sustainable energy storage.However,the slow conversion and severe shuttle of polysulfides(LiPSs)result in rapid p...Lithium-sulfur(Li-S)batteries are considered a potential candidate for next-generation energy-dense and sustainable energy storage.However,the slow conversion and severe shuttle of polysulfides(LiPSs)result in rapid performance degradation over long-term cycling.Herein,we report a high-entropy single-atom(HE-SA)catalyst to regulate the multi-step conversion of LiPS to attain a high-performance Li-S battery.Both the density functional theory calculations and the experimental results prove that the Fe atomic site with high spin configurations strongly interacts with Li_(2)S_(4)through d-p and s-p synergistic orbital hybridization which facilitates the reduction of LiPS.Moreover,S-dominant p-d hybridization between Li_(2)S and a high-spin Mn site weakens the Li-S bond and facilitates the rapid sulfur evolution reaction.Consequently,the Li-S battery with a bifunctional HE-SA catalyst shows an ultralow capacity decay of 0.026% per cycle over 1900 cycles at 1 C.This work proposes a high-entropy strategy for sculpting electronic structures to enable spin and orbital hybridization modulation in advanced catalysts toward longcycling Li-S batteries.展开更多
The introduction of materials with dual-functionalities,i.e.,the catalytic(adsorption)features to inhibit shuttle effects at the cathode side,and the capability to facilitate homogenous Li-ion fluxes at the anode side...The introduction of materials with dual-functionalities,i.e.,the catalytic(adsorption)features to inhibit shuttle effects at the cathode side,and the capability to facilitate homogenous Li-ion fluxes at the anode side,is a promising strategy to realize high performance lithium-sulfur batteries(LSBs).Herein,a facile and rational organic“ligand-induced”(trimesic acid(TMA))transformation tactic is proposed,which achieves the regulation of electronic performance and d-band center of bimetallic oxides(NiFe_(2)O_(4))to promote bidirectional sulfur conversion kinetics and stabilize the Li plating/striping during the charge/discharge process.The battery assembled with NiFe_(2)O_(4)-TMA modified separator exhibits a remarkable initial specific capacity of 1476.6 mAh·g^(-1)at 0.1 C,outstanding rate properties(661.1 mAh·g^(-1)at 8.0 C),and excellent cycling ability.The“ligand-induced”transformation tactic proposed in this work will open a whole new possibility for tuning the electronic structure and d-band center to enhance the performance of LSBs.展开更多
The use of lithium-sulfur(Li-S)batteries is limited by sulfur redox reactions involving multi-phase transformations,especially at low-temperatures.To address this issue,we report a material(FCNS@NCFs)consisting of nit...The use of lithium-sulfur(Li-S)batteries is limited by sulfur redox reactions involving multi-phase transformations,especially at low-temperatures.To address this issue,we report a material(FCNS@NCFs)consisting of nitrogen-doped carbon fibers loaded with a ternary metal sulf-ide((Fe,Co,Ni)_(9)S_(8))for use as the sulfur host in Li-S batteries.This materi-al was prepared using transfer blot filter paper as the carbon precursor,thiourea as the source of nitrogen and sulfur,and FeCl_(3)·6H_(2)O,CoCl_(2)·6H_(2)O and NiCl_(2)·6H_(2)O as the metal ion sources.It was synthesized by an impreg-nation method followed by calcination.The nitrogen doping significantly in-creased the conductivity of the host,and the metal sulfides have excellent catalytic activities.Theoretical calculations,and adsorption and deposition experiments show that active sites on the surface of FCNS@NCFs selectively adsorb polysulfides,facilitate rapid adsorption and conversion,prevent cathode passivation and inhib-it the polysulfide shuttling.The FCNS@NCFs used as the sulfur host has excellent electrochemical properties.Its initial dis-charge capacity is 1639.0 mAh g^(−1) at 0.2 C and room temperature,and it remains a capacity of 1255.1 mAh g^(−1) after 100 cycles.At−20~C,it has an initial discharge capacity of 1578.5 mAh g^(−1) at 0.2 C,with a capacity of 867.5 mAh g^(−1) after 100 cycles.Its excellent performance at both ambient and low temperatures suggests a new way to produce high-performance low-temper-ature Li-S batteries.展开更多
Metal-sulfur electrochemistry represents a promising energy storage technology due to the natural abundance and unparalleled theoretical specific capacity of 1675 mAh g^(-1)of sulfur based on two-electron redox reacti...Metal-sulfur electrochemistry represents a promising energy storage technology due to the natural abundance and unparalleled theoretical specific capacity of 1675 mAh g^(-1)of sulfur based on two-electron redox reaction(S^(0)■S^(2-)).Commercially viable metal-sulfur batteries(MSBs)are hindered by sluggish sulfur conversion kinetics,which reduce the utilization efficiency of sulfur and lead to polysulfide shuttling.Single-atom catalysts(SACs)exhibit specific catalytic activity,a high atomic utilization ratio,and flexible selectivity,and are considered exceptional electrocatalysts for addressing the intractable challenges encountered by the MSBs.This review summarizes the recent progress in SACs for boosting the sulfur electrochemistry in MSBs,focusing on sulfur host materials,modified separators and functional interlayers,and analyzes the in-depth mechanisms of SACs.Moreover,the correlation between the coordination environments and the intrinsic activity of SACs is discussed.Finally,the main challenges and potential research directions of SACs for high-energy-density and long-life MSBs are outlined.This study provides significant guidance for constructing novel SACs that can accelerate the sulfur conversion kinetics in MSBs.展开更多
The rechargeable Mg-S batteries are attractive because of their resource abundances of Mg and S,high volumetric energy density,and less dendrite property of Mg anodes.However,the development is barred by the intrinsic...The rechargeable Mg-S batteries are attractive because of their resource abundances of Mg and S,high volumetric energy density,and less dendrite property of Mg anodes.However,the development is barred by the intrinsic low electronic conductivity of S and the discharge products as well as the lack of understanding the hidden electrochemical kinetics.Here,a Co_(3)S_(4)@MXene heterostructure is proposed as effective sulfur host for reversible Mg-S batteries.XPS results and density functional theory(DFT)calculation confirm that the chemical interaction between the decorated Co_(3)S_(4)nanocrystals host and polysulfide intermediates could well absorb and catalyze the polysulfides conversion,thus improve the electrochemical redox kinetics.Meanwhile,the MXene matrix could promote Mg ion diffusion dynamics greatly.As a result,the developed Mg-S batteries using the Co_(3)S_(4)@MXene-S as the cathode material could demonstrate high sulfur utilization with specific capacity of 1220 mAh g^(-1) and retain a capacity of 528 mAh g^(-1) after 100 cycles,together with a satisfactory rate performance even at 2 C.This work shed light on the advanced cathode design for reversible high energy Mg-S batteries.展开更多
Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slo...Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slow redox reaction kinetics seriously hamper the commercialization of Li-S batteries.In this study,a defect-rich single-atom catalyst with an oversaturated asymmetric Fe-N_(5)coordination structure anchored in defective g-C_(3)N_(4)(C_(3)N_(4)-Fe@rGO)is designed via an absorption-pyrolysis strategy.The two-dimensional(2D)conducting C_(3)N_(4)@graphene structure with abundant defect sites accelerates the trans-fer and transportation of lithium ions and electrons.The oversaturated asymmetric Fe-N_(5)coordination structure effectively improves the adsorbility of LiPSs and accelerates the redox kinetics of sulfur species.Hence,the Li-S cell with a C_(3)N_(4)-Fe@rGO modified separator reveals a high initial capacity(1197.1 mAh g^(-1) at 0.2 C)and a low capacity decay rate(0.037%per cycle after 900 cycles at 1 C).Even at high sulfur loading and extreme temperatures of 0℃,it also shows good cycling performance.This work creates ideas for synthesizing oversaturated single-atom coordination environments and an efficient route to the practical realization of the Li-S batteries.展开更多
Solid-state lithium-sulfur(Li-S)batteries are deemed next-generation energy storage systems based on their high theoretical energy density and enhanced safety.However,challenges such as sluggish sulfur conversion kine...Solid-state lithium-sulfur(Li-S)batteries are deemed next-generation energy storage systems based on their high theoretical energy density and enhanced safety.However,challenges such as sluggish sulfur conversion kinetics and the polysulfide shuttle effect remain critical obstacles to their practical deployment.Herein,a novel surface-modified garnet-type Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)solid-state electrolyte(SSE)is proposed,utilizing a mono-lacunary Keggin-type polyoxometalate(PW11)to overcome the aforementioned limitations.The optimized PW11-LLZTO composite electrolyte exhibits a uniform surface morphology and improved interfacial stability with lithium metal.Symmetric Li/PW11-LLZTO/Li cells achieve a critical current density of 0.9 mA cm^(−2) and stable cycling over 800 h with low polarization.When applied in quasi-solid-state Li-S batteries,the PW11-LLZTO SSE significantly suppresses polysulfide shuttling,enhances sulfur redox kinetics,and delivers a superior reversible capacity of 619.4 mAh g^(−1) after 200 cycles at 1C.Density functional theory(DFT)calculations reveal that the lacunary structure alters the electron cloud density of oxygen atoms in PW11,resulting in enhanced nucleophilicity and stronger Lewis basicity,which in turn strengthens its binding interaction with Li^(+).Therefore,the mono-lacunary PW11 exhibits efficient Lewis acid-base interactions between the oxygen atoms of polyoxoanions and Li moieties in polysulfides,thereby facilitating the conversion kinetics of polysulfides.This work demonstrates the great potential of the lacunary strategy of polyoxometalates in designing high-performance SSEs for advanced quasi-solid-state Li-S batteries.展开更多
Additives could improve composting performance and reduce gaseous emission,but few studies have explored the synergistic of additives on H_(2)S emission and compost maturity.This research aims to make an investigation...Additives could improve composting performance and reduce gaseous emission,but few studies have explored the synergistic of additives on H_(2)S emission and compost maturity.This research aims to make an investigation about the effects of chemical additives and mature compost on H_(2)S emission and compost maturity of kitchen waste composting.The results showed that additives increased the germination index value and H_(2)S emission reduction over 15 days and the treatment with both chemical additives and mature compost achieved highest germination index value and H_(2)S emission reduction(85%).Except for the treatment with only chemical additives,the total sulfur content increased during the kitchen waste composting.The proportion of effective sulfur was higher with the addition of chemical additives,compared with other groups.The relative abundance of H_(2)S-formation bacterial(Desulfovibrio)was reduced and the relative abundance of bacterial(Pseudomonas and Paracoccus),which could convert sulfur-containing substances and H_(2)S to sulfate was improved with additives.In the composting process with both chemical additives and mature compost,the relative abundance of Desulfovibrio was lowest,while the relative abundance of Pseudomonas and Paracoccus was highest.Taken together,the chemical additives and mature compost achieved H_(2)S emission reduction by regulating the dynamics of microbial community.展开更多
ABSTRACT:Lithium–sulfur(Li–S)batteries are regarded as highly promising next-generation energy storage technologies due to their high theoretical specific energy(2600 Wh·kg^(−1)),low cost,and the abundance of s...ABSTRACT:Lithium–sulfur(Li–S)batteries are regarded as highly promising next-generation energy storage technologies due to their high theoretical specific energy(2600 Wh·kg^(−1)),low cost,and the abundance of sulfur.However,their practical application is severely hindered by the shuttle effect of soluble lithium polysulfides(LiPSs)and sluggish sulfur redox kinetics,leading to rapid capacity degradation.The inherent electronic structure of CoSe_(2),employed as a catalyst,restricts its catalytic efficiency.This work proposed a synergistic strategy combining nickel doping and heterointerface engineering to modulate the electronic structure of CoSe_(2) and enhance bidirectional sulfur electrochemistry.Combined structural characterization and density functional theory(DFT)calculations demonstrated that Ni doping induced lattice distortion in CoSe_(2),forming shortened Ni–Se bonds.This prompted a shift of the Co 3d band towards the Fermi level,thereby significantly enhancing the intrinsic conductivity of the material.Concurrently,lattice defects enhanced the availability of active sites for Li_(2)S nucleation.Augmented by the dual physical/chemical confinement of LiPSs provided by the N-doped carbon skeleton,this design established an“adsorption-catalysis”synergistic mechanism,effectively suppressing the shuttle effect and accelerating conversion kinetics.The fabricated Ni-CoSe_(2)/nitrogen-doped carbon(NC)-based Li–S battery delivered a high initial specific capacity of 1219 mAh·g^(−1) at 0.1 C and maintained an ultralow capacity decay rate of 0.064%per cycle over 1000 cycles at 1 C.Notably,the battery also exhibited exceptional cycling stability under lean electrolyte and high sulfur loading conditions.This study elucidated the enhancement mechanism through electronic structure modulation via integrated experimental and theoretical approaches,providing a novel design concept for advanced energy storage materials.展开更多
Lithium-sulfur(Li-S)batteries are regarded as one of the most promising next-generation energy storage systems due to their high theoretical energy density and low material cost.However,the conventional ether-based el...Lithium-sulfur(Li-S)batteries are regarded as one of the most promising next-generation energy storage systems due to their high theoretical energy density and low material cost.However,the conventional ether-based electrolytes of Li-S batteries are extremely flammable and have high solubility of lithium polysulfides(LiPS),resulting in a high safety risk and a poor life cycle.Herein,we report an ether/carbonate co-solvent fluorinated electrolyte with a special solvation sheath of Li^(+),which can prevent the formation of dissoluble long-chain LiPS of the sulfur cathode,restrict Li dendrite growth at the anode side,and show fire resistance in combustion experiments.As a result,the proposed Li-S batteries with 70 wt%sulfur content in its cathode deliver stable life cycle,low self-discharge ratio,and intrinsic safety.Therefore,the unique passivation characteristics of the designed fluorinated electrolyte break several critical limitations of the traditional“liquid phase”-based Li-S batteries,offering a facile and promising way to develop long-life and high-safety Li-S batteries.展开更多
Lithium-sulfur batteries are regarded as promising next-generation energy storage batteries for their ultra-high theoretical energy density.However,the complex sulfur electrode process with sluggish sulfur conversion ...Lithium-sulfur batteries are regarded as promising next-generation energy storage batteries for their ultra-high theoretical energy density.However,the complex sulfur electrode process with sluggish sulfur conversion reactions is a critical issue for lithiumsulfur batteries,in which catalytic interfacial reactions and accelerated lithium-ion diffusion are the key factors.Our previous work has shown that implanting functional molecules with multiple redox properties in the electrode can break through the conventional diffusion layer constraints and achieve forced convection.In this work,a functionalized complex molecule,methylene blue anthraquinone-2-sulfonate(MB-AQ),with multiple redox activities as well as abundant active sites,was synthesized and introduced into the sulfur cathode.In addition to accelerating the transport of lithium ions by reversible inhaling and exhaling lithium ions,the MB-AQ can combine polysulfides by its active sites to accelerate sulfur conversion reactions.Benefiting from two functions of accelerating ion diffusion and catalyzing interfacial reactions,MB-AQ/reduced graphene oxide(rGO)/S cathode can achieve high initial capacities of 884 and 674 mAh·g^(−1)with stable cycling of 700 and 1,000 times at 1 and 4 C,respectively.It is worth mentioning that the capacity of 462 mAh·g^(−1)can be achieved even at a high current density of 6 C.This work provides a new approach to enhancing the sulfur cathode process.展开更多
基金Institute of Technology Research Fund Program for Young Scholars21C Innovation Laboratory Contemporary Amperex Technology Co.,Limited,Ninde, 352100, China (21C–OP-202314)。
文摘Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox dynamics.Herein,we supply a strategy to optimize the electron structure of Ni_(2)P by concurrently introducing B-doped atoms and P vacancies in Ni_(2)P (Vp-B-Ni_(2)P),thereby enhancing the bidirectional sulfur conversion.The study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni_(2)P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides (LiPSs) as well as expediting the bidirectional conversion kinetics of sulfur species.Meanwhile,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni_(2)P selectively promotes Li2S dissolution and nucleation processes.Thus,the Li-S batteries with Vp-B-Ni_(2)P-separators present outstanding rate ability of 777 m A h g^(-1)at 5 C and high areal capacity of 8.03 mA h cm^(-2)under E/S of 5μL mg^(-1)and sulfur loading of 7.20 mg cm^(-2).This work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.
基金supported by the National Natural Science Foundation of China(52302240)the Macao Young Scholars Program(AM2023011)the Yuanguang Scholars Program,Hebei University of Technology(282022554)。
文摘Lithium-sulfur(Li-S)batteries are considered a potential candidate for next-generation energy-dense and sustainable energy storage.However,the slow conversion and severe shuttle of polysulfides(LiPSs)result in rapid performance degradation over long-term cycling.Herein,we report a high-entropy single-atom(HE-SA)catalyst to regulate the multi-step conversion of LiPS to attain a high-performance Li-S battery.Both the density functional theory calculations and the experimental results prove that the Fe atomic site with high spin configurations strongly interacts with Li_(2)S_(4)through d-p and s-p synergistic orbital hybridization which facilitates the reduction of LiPS.Moreover,S-dominant p-d hybridization between Li_(2)S and a high-spin Mn site weakens the Li-S bond and facilitates the rapid sulfur evolution reaction.Consequently,the Li-S battery with a bifunctional HE-SA catalyst shows an ultralow capacity decay of 0.026% per cycle over 1900 cycles at 1 C.This work proposes a high-entropy strategy for sculpting electronic structures to enable spin and orbital hybridization modulation in advanced catalysts toward longcycling Li-S batteries.
基金This work was financially supported by the Natural Science Foundation of Guangdong Province(No.2019A1515011727)the Open Fund of the Guangdong Provincial Key Laboratory of Advance Energy Storage Materials.We also acknowledge the fund of Natural Science Foundation of Hubei Province(No.2021CFB011)the National Natural Science Foundation of China(Nos.52104309 and 52161033).
文摘The introduction of materials with dual-functionalities,i.e.,the catalytic(adsorption)features to inhibit shuttle effects at the cathode side,and the capability to facilitate homogenous Li-ion fluxes at the anode side,is a promising strategy to realize high performance lithium-sulfur batteries(LSBs).Herein,a facile and rational organic“ligand-induced”(trimesic acid(TMA))transformation tactic is proposed,which achieves the regulation of electronic performance and d-band center of bimetallic oxides(NiFe_(2)O_(4))to promote bidirectional sulfur conversion kinetics and stabilize the Li plating/striping during the charge/discharge process.The battery assembled with NiFe_(2)O_(4)-TMA modified separator exhibits a remarkable initial specific capacity of 1476.6 mAh·g^(-1)at 0.1 C,outstanding rate properties(661.1 mAh·g^(-1)at 8.0 C),and excellent cycling ability.The“ligand-induced”transformation tactic proposed in this work will open a whole new possibility for tuning the electronic structure and d-band center to enhance the performance of LSBs.
基金partially supported by National Natural Science Foundation of China(52172250)Institute of Process Engineering(IPE)Project for Frontier Basic Research(QYJC-2023-06)。
文摘The use of lithium-sulfur(Li-S)batteries is limited by sulfur redox reactions involving multi-phase transformations,especially at low-temperatures.To address this issue,we report a material(FCNS@NCFs)consisting of nitrogen-doped carbon fibers loaded with a ternary metal sulf-ide((Fe,Co,Ni)_(9)S_(8))for use as the sulfur host in Li-S batteries.This materi-al was prepared using transfer blot filter paper as the carbon precursor,thiourea as the source of nitrogen and sulfur,and FeCl_(3)·6H_(2)O,CoCl_(2)·6H_(2)O and NiCl_(2)·6H_(2)O as the metal ion sources.It was synthesized by an impreg-nation method followed by calcination.The nitrogen doping significantly in-creased the conductivity of the host,and the metal sulfides have excellent catalytic activities.Theoretical calculations,and adsorption and deposition experiments show that active sites on the surface of FCNS@NCFs selectively adsorb polysulfides,facilitate rapid adsorption and conversion,prevent cathode passivation and inhib-it the polysulfide shuttling.The FCNS@NCFs used as the sulfur host has excellent electrochemical properties.Its initial dis-charge capacity is 1639.0 mAh g^(−1) at 0.2 C and room temperature,and it remains a capacity of 1255.1 mAh g^(−1) after 100 cycles.At−20~C,it has an initial discharge capacity of 1578.5 mAh g^(−1) at 0.2 C,with a capacity of 867.5 mAh g^(−1) after 100 cycles.Its excellent performance at both ambient and low temperatures suggests a new way to produce high-performance low-temper-ature Li-S batteries.
基金financial support from the National Natural Science Foundation of China(No.22379001 and 22309003)the Natural Science Research Project of Anhui Province Education department(No.2022AH030046)the Top Young Talents of Anhui University of Technology,the Young Scholars of the Introduction and Education of Talents in Anhui Province,and the Scientific Research Foundation of Anhui University of Technology for Talent Introduction。
文摘Metal-sulfur electrochemistry represents a promising energy storage technology due to the natural abundance and unparalleled theoretical specific capacity of 1675 mAh g^(-1)of sulfur based on two-electron redox reaction(S^(0)■S^(2-)).Commercially viable metal-sulfur batteries(MSBs)are hindered by sluggish sulfur conversion kinetics,which reduce the utilization efficiency of sulfur and lead to polysulfide shuttling.Single-atom catalysts(SACs)exhibit specific catalytic activity,a high atomic utilization ratio,and flexible selectivity,and are considered exceptional electrocatalysts for addressing the intractable challenges encountered by the MSBs.This review summarizes the recent progress in SACs for boosting the sulfur electrochemistry in MSBs,focusing on sulfur host materials,modified separators and functional interlayers,and analyzes the in-depth mechanisms of SACs.Moreover,the correlation between the coordination environments and the intrinsic activity of SACs is discussed.Finally,the main challenges and potential research directions of SACs for high-energy-density and long-life MSBs are outlined.This study provides significant guidance for constructing novel SACs that can accelerate the sulfur conversion kinetics in MSBs.
基金This work was financially supported by the National Natu-ral Science Foundation of China(No.21603019)the Opening Project of State Key Laboratory of High Performance Ce-ramics and Superfine Microstructure(SKL201807SIC)program for the Hundred Talents Program of Chongqing University.
文摘The rechargeable Mg-S batteries are attractive because of their resource abundances of Mg and S,high volumetric energy density,and less dendrite property of Mg anodes.However,the development is barred by the intrinsic low electronic conductivity of S and the discharge products as well as the lack of understanding the hidden electrochemical kinetics.Here,a Co_(3)S_(4)@MXene heterostructure is proposed as effective sulfur host for reversible Mg-S batteries.XPS results and density functional theory(DFT)calculation confirm that the chemical interaction between the decorated Co_(3)S_(4)nanocrystals host and polysulfide intermediates could well absorb and catalyze the polysulfides conversion,thus improve the electrochemical redox kinetics.Meanwhile,the MXene matrix could promote Mg ion diffusion dynamics greatly.As a result,the developed Mg-S batteries using the Co_(3)S_(4)@MXene-S as the cathode material could demonstrate high sulfur utilization with specific capacity of 1220 mAh g^(-1) and retain a capacity of 528 mAh g^(-1) after 100 cycles,together with a satisfactory rate performance even at 2 C.This work shed light on the advanced cathode design for reversible high energy Mg-S batteries.
基金supported by the National Natural Science Foundation of China(Nos.U21A2060 and 22178116)the Natural Science Foundation of Shanghai(No.22ZR1417400)the Fundamental Research Funds for the Central Universities(Nos.222201817001,50321041918013,JKA01221601,JKD01241701).
文摘Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slow redox reaction kinetics seriously hamper the commercialization of Li-S batteries.In this study,a defect-rich single-atom catalyst with an oversaturated asymmetric Fe-N_(5)coordination structure anchored in defective g-C_(3)N_(4)(C_(3)N_(4)-Fe@rGO)is designed via an absorption-pyrolysis strategy.The two-dimensional(2D)conducting C_(3)N_(4)@graphene structure with abundant defect sites accelerates the trans-fer and transportation of lithium ions and electrons.The oversaturated asymmetric Fe-N_(5)coordination structure effectively improves the adsorbility of LiPSs and accelerates the redox kinetics of sulfur species.Hence,the Li-S cell with a C_(3)N_(4)-Fe@rGO modified separator reveals a high initial capacity(1197.1 mAh g^(-1) at 0.2 C)and a low capacity decay rate(0.037%per cycle after 900 cycles at 1 C).Even at high sulfur loading and extreme temperatures of 0℃,it also shows good cycling performance.This work creates ideas for synthesizing oversaturated single-atom coordination environments and an efficient route to the practical realization of the Li-S batteries.
基金support from the National Natural Science Foundation of China(22201098 and 22471095)the Natural Science Foundation of Shandong Province(ZR2024QB211)+1 种基金the Jinan City“New University 20”Project(202228113)the Science and Technology Program of the University of Jinan(XBS2404).
文摘Solid-state lithium-sulfur(Li-S)batteries are deemed next-generation energy storage systems based on their high theoretical energy density and enhanced safety.However,challenges such as sluggish sulfur conversion kinetics and the polysulfide shuttle effect remain critical obstacles to their practical deployment.Herein,a novel surface-modified garnet-type Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)solid-state electrolyte(SSE)is proposed,utilizing a mono-lacunary Keggin-type polyoxometalate(PW11)to overcome the aforementioned limitations.The optimized PW11-LLZTO composite electrolyte exhibits a uniform surface morphology and improved interfacial stability with lithium metal.Symmetric Li/PW11-LLZTO/Li cells achieve a critical current density of 0.9 mA cm^(−2) and stable cycling over 800 h with low polarization.When applied in quasi-solid-state Li-S batteries,the PW11-LLZTO SSE significantly suppresses polysulfide shuttling,enhances sulfur redox kinetics,and delivers a superior reversible capacity of 619.4 mAh g^(−1) after 200 cycles at 1C.Density functional theory(DFT)calculations reveal that the lacunary structure alters the electron cloud density of oxygen atoms in PW11,resulting in enhanced nucleophilicity and stronger Lewis basicity,which in turn strengthens its binding interaction with Li^(+).Therefore,the mono-lacunary PW11 exhibits efficient Lewis acid-base interactions between the oxygen atoms of polyoxoanions and Li moieties in polysulfides,thereby facilitating the conversion kinetics of polysulfides.This work demonstrates the great potential of the lacunary strategy of polyoxometalates in designing high-performance SSEs for advanced quasi-solid-state Li-S batteries.
基金supported by the National Natural Science Foundation of China(Nos.32071552,42007031,31960013,and 31800378)the Open Research Fund from the Key Laboratory of Forest Ecology in Tibet Plateau(Tibet Agriculture&Animal Husbandry University),Ministry of Education,China(No.XZAJYBSYS-2020-02)+2 种基金the Independent Research Project of Science and Technology Innovation Base in Tibet Autonomous Region(No.XZ2022JR0007G)Suzhou Science and Technology Plan Project(No.SS20200)Ministry of Urban-Rural Development and Housing Technology Demonstration Project(No.S20220395)。
文摘Additives could improve composting performance and reduce gaseous emission,but few studies have explored the synergistic of additives on H_(2)S emission and compost maturity.This research aims to make an investigation about the effects of chemical additives and mature compost on H_(2)S emission and compost maturity of kitchen waste composting.The results showed that additives increased the germination index value and H_(2)S emission reduction over 15 days and the treatment with both chemical additives and mature compost achieved highest germination index value and H_(2)S emission reduction(85%).Except for the treatment with only chemical additives,the total sulfur content increased during the kitchen waste composting.The proportion of effective sulfur was higher with the addition of chemical additives,compared with other groups.The relative abundance of H_(2)S-formation bacterial(Desulfovibrio)was reduced and the relative abundance of bacterial(Pseudomonas and Paracoccus),which could convert sulfur-containing substances and H_(2)S to sulfate was improved with additives.In the composting process with both chemical additives and mature compost,the relative abundance of Desulfovibrio was lowest,while the relative abundance of Pseudomonas and Paracoccus was highest.Taken together,the chemical additives and mature compost achieved H_(2)S emission reduction by regulating the dynamics of microbial community.
基金supported in part by the National Natural Science Foundation of China(No.52303303)Henan Province Science and Technology Research and Development Joint Fund(Nos.235200810047 and 235200810003)+1 种基金Central Plains Academician Fund Project(No.231723008)the Scientific Research Foundation of Henan Academy of Sciences(No.241823159)。
文摘ABSTRACT:Lithium–sulfur(Li–S)batteries are regarded as highly promising next-generation energy storage technologies due to their high theoretical specific energy(2600 Wh·kg^(−1)),low cost,and the abundance of sulfur.However,their practical application is severely hindered by the shuttle effect of soluble lithium polysulfides(LiPSs)and sluggish sulfur redox kinetics,leading to rapid capacity degradation.The inherent electronic structure of CoSe_(2),employed as a catalyst,restricts its catalytic efficiency.This work proposed a synergistic strategy combining nickel doping and heterointerface engineering to modulate the electronic structure of CoSe_(2) and enhance bidirectional sulfur electrochemistry.Combined structural characterization and density functional theory(DFT)calculations demonstrated that Ni doping induced lattice distortion in CoSe_(2),forming shortened Ni–Se bonds.This prompted a shift of the Co 3d band towards the Fermi level,thereby significantly enhancing the intrinsic conductivity of the material.Concurrently,lattice defects enhanced the availability of active sites for Li_(2)S nucleation.Augmented by the dual physical/chemical confinement of LiPSs provided by the N-doped carbon skeleton,this design established an“adsorption-catalysis”synergistic mechanism,effectively suppressing the shuttle effect and accelerating conversion kinetics.The fabricated Ni-CoSe_(2)/nitrogen-doped carbon(NC)-based Li–S battery delivered a high initial specific capacity of 1219 mAh·g^(−1) at 0.1 C and maintained an ultralow capacity decay rate of 0.064%per cycle over 1000 cycles at 1 C.Notably,the battery also exhibited exceptional cycling stability under lean electrolyte and high sulfur loading conditions.This study elucidated the enhancement mechanism through electronic structure modulation via integrated experimental and theoretical approaches,providing a novel design concept for advanced energy storage materials.
基金financially supported by the National Key R&D Program of China (2018YFB0905400)the National Natural Science Foundation of China (51972131 and 51632001)
文摘Lithium-sulfur(Li-S)batteries are regarded as one of the most promising next-generation energy storage systems due to their high theoretical energy density and low material cost.However,the conventional ether-based electrolytes of Li-S batteries are extremely flammable and have high solubility of lithium polysulfides(LiPS),resulting in a high safety risk and a poor life cycle.Herein,we report an ether/carbonate co-solvent fluorinated electrolyte with a special solvation sheath of Li^(+),which can prevent the formation of dissoluble long-chain LiPS of the sulfur cathode,restrict Li dendrite growth at the anode side,and show fire resistance in combustion experiments.As a result,the proposed Li-S batteries with 70 wt%sulfur content in its cathode deliver stable life cycle,low self-discharge ratio,and intrinsic safety.Therefore,the unique passivation characteristics of the designed fluorinated electrolyte break several critical limitations of the traditional“liquid phase”-based Li-S batteries,offering a facile and promising way to develop long-life and high-safety Li-S batteries.
基金supported by the National Natural Science Foundation of China(Nos.U1805254,21773192,22072117,and 22179112).
文摘Lithium-sulfur batteries are regarded as promising next-generation energy storage batteries for their ultra-high theoretical energy density.However,the complex sulfur electrode process with sluggish sulfur conversion reactions is a critical issue for lithiumsulfur batteries,in which catalytic interfacial reactions and accelerated lithium-ion diffusion are the key factors.Our previous work has shown that implanting functional molecules with multiple redox properties in the electrode can break through the conventional diffusion layer constraints and achieve forced convection.In this work,a functionalized complex molecule,methylene blue anthraquinone-2-sulfonate(MB-AQ),with multiple redox activities as well as abundant active sites,was synthesized and introduced into the sulfur cathode.In addition to accelerating the transport of lithium ions by reversible inhaling and exhaling lithium ions,the MB-AQ can combine polysulfides by its active sites to accelerate sulfur conversion reactions.Benefiting from two functions of accelerating ion diffusion and catalyzing interfacial reactions,MB-AQ/reduced graphene oxide(rGO)/S cathode can achieve high initial capacities of 884 and 674 mAh·g^(−1)with stable cycling of 700 and 1,000 times at 1 and 4 C,respectively.It is worth mentioning that the capacity of 462 mAh·g^(−1)can be achieved even at a high current density of 6 C.This work provides a new approach to enhancing the sulfur cathode process.
