Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferio...Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferior lithium metal anode(LMA) compatibility and sluggish Li^(+) desolvation.Here,we demonstrate that cyclopentylmethyl ether(CPME) based diluted high-concentration electrolyte(DHCE)enables-60℃ LMBs operation.By leveraging the loose coordination between Li^(+) and CPME,such developed electrolyte boosts the formation of ion clusters to derive anion-dominant interfacial chemistry for enhancing LMA compatibility and greatly accelerates Li^(+) desolvation kinetics.The resulting electrolyte demonstrates high Coulombic efficiencies(CE),providing over 99.5%,99.1%,98.5% and 95% at 25,-20,-40,and-60℃respectively.The assembled Li-S battery exhibits remarkable cyclic stability in-20,and-40℃ at 0.2 C charging and 0.5 C discharging.Even at-60℃,Li-S cell with this designed electrolyte retains> 70% of the initial capacity over 170 cycles.Besides,lithium metal coin cell and pouch cell with10 mg cm^(-2) high S cathode loading exhibit cycling stability at-20℃.This work offers an opportunity for rational designing electrolytes toward low temperature LMBs.展开更多
Reasonably designing composition and nanostructure to enhance the stability of bifunctional catalysts is highly desired for rechargeable Zn-air batteries(ZABs).Here,porous carbon nanofibers(CNFs)encapsulated CoNiFe al...Reasonably designing composition and nanostructure to enhance the stability of bifunctional catalysts is highly desired for rechargeable Zn-air batteries(ZABs).Here,porous carbon nanofibers(CNFs)encapsulated CoNiFe alloy nanoparticles(NPs)(CoNiFe/CNFs)were synthesized controllably by in-situ growth and cation etching.Electrochemical tests indicated that CoNiFe/CNFs exhibited excellent bifunctional performances in both oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Using CoNiFe/CNFs as bifunctional catalysts,the assembled ZABs presented ultralong durability up to 1050 and 660 h at 5 and 25 mA cm^(-2),respectively.The assembled flexible solid-state ZABs-based polyacrylamide(PAM)hydrogel exhibited a power density of 62.9 mW cm^(-2) and 66 h durability at 2 mA cm^(-2) under ultralow temperature of -40℃.The excellent performance of CoNiFe/CNFs was ascribed to the encapsulation of CNFs by the alloy NPs and the synergy of multi-metals in the alloy NPs,because the encapsulation could suppress alloy spillage and agglomeration and protect the catalytic sites from electrolyte deterioration,thereby boosting the durability of the resulting ZABs.展开更多
Novel small sulfur heterocyclic quinones(6a,16adihydrobenzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,7,9,14,16,18-hexaone(4S6Q)and benzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,9,14,18-t...Novel small sulfur heterocyclic quinones(6a,16adihydrobenzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,7,9,14,16,18-hexaone(4S6Q)and benzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,9,14,18-tetraone(4S4Q))are developed by molecule structural design method and as cathode for aqueous zincorganic batteries.The conjugated thioether(–S–)bonds as connected units not only improve the conductivity of compounds but also inhibit their dissolution by both extendedπ-conjugated plane and constructed flexible molecular skeleton.Hence,the Zn//4S6Q and Zn//4S4Q batteries exhibit satisfactory electrochemical performance based on 3.5 mol L-1(M)Zn(ClO4)2electrolyte.For instance,the Zn//4S6Q battery obtains 240 and 208.6 mAh g^(-1)of discharge capacity at 150 mA g^(-1)and 30 A g^(-1),respectively.The excellent rate capability is ascribed to the fast reaction kinetics.This system displays a superlong life of 20,000 cycles with no capacity fading at 3 A g^(-1).Additionally,the H+-storage mechanism of the 4S6Q compound is demonstrated by ex situ analyses and density functional theory calculations.Impressively,the battery can normally work at-60℃benefiting from the anti-freezing electrolyte and maintain a high discharge capacity of 201.7 mAh g^(-1),which is 86.2%of discharge capacity at 25℃.The cutting-edge electrochemical performances of these novel compounds make them alternative electrode materials for Zn-organic batteries.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21975087,22008082)。
文摘Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferior lithium metal anode(LMA) compatibility and sluggish Li^(+) desolvation.Here,we demonstrate that cyclopentylmethyl ether(CPME) based diluted high-concentration electrolyte(DHCE)enables-60℃ LMBs operation.By leveraging the loose coordination between Li^(+) and CPME,such developed electrolyte boosts the formation of ion clusters to derive anion-dominant interfacial chemistry for enhancing LMA compatibility and greatly accelerates Li^(+) desolvation kinetics.The resulting electrolyte demonstrates high Coulombic efficiencies(CE),providing over 99.5%,99.1%,98.5% and 95% at 25,-20,-40,and-60℃respectively.The assembled Li-S battery exhibits remarkable cyclic stability in-20,and-40℃ at 0.2 C charging and 0.5 C discharging.Even at-60℃,Li-S cell with this designed electrolyte retains> 70% of the initial capacity over 170 cycles.Besides,lithium metal coin cell and pouch cell with10 mg cm^(-2) high S cathode loading exhibit cycling stability at-20℃.This work offers an opportunity for rational designing electrolytes toward low temperature LMBs.
基金supported by the National Natural Science Foundation of China(grant no.52103250)the Opening Foundation of State Key Laboratory of Organic-Inorganic Composites,China(grant no.oic-202301001)the Fundamental Research Funds for the Central Universities,China(grant no.buctrc202213).
文摘Reasonably designing composition and nanostructure to enhance the stability of bifunctional catalysts is highly desired for rechargeable Zn-air batteries(ZABs).Here,porous carbon nanofibers(CNFs)encapsulated CoNiFe alloy nanoparticles(NPs)(CoNiFe/CNFs)were synthesized controllably by in-situ growth and cation etching.Electrochemical tests indicated that CoNiFe/CNFs exhibited excellent bifunctional performances in both oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Using CoNiFe/CNFs as bifunctional catalysts,the assembled ZABs presented ultralong durability up to 1050 and 660 h at 5 and 25 mA cm^(-2),respectively.The assembled flexible solid-state ZABs-based polyacrylamide(PAM)hydrogel exhibited a power density of 62.9 mW cm^(-2) and 66 h durability at 2 mA cm^(-2) under ultralow temperature of -40℃.The excellent performance of CoNiFe/CNFs was ascribed to the encapsulation of CNFs by the alloy NPs and the synergy of multi-metals in the alloy NPs,because the encapsulation could suppress alloy spillage and agglomeration and protect the catalytic sites from electrolyte deterioration,thereby boosting the durability of the resulting ZABs.
基金the National Natural Science Foundation of China(22279063 and 21835004)the National Key R&D Program of China(2016YFB0901500)+1 种基金Ministry of Education of China(B12015 and IRT13R30)the Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Novel small sulfur heterocyclic quinones(6a,16adihydrobenzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,7,9,14,16,18-hexaone(4S6Q)and benzo[b]naphtho[2′,3′:5,6][1,4]dithiino[2,3-i]thianthrene-5,9,14,18-tetraone(4S4Q))are developed by molecule structural design method and as cathode for aqueous zincorganic batteries.The conjugated thioether(–S–)bonds as connected units not only improve the conductivity of compounds but also inhibit their dissolution by both extendedπ-conjugated plane and constructed flexible molecular skeleton.Hence,the Zn//4S6Q and Zn//4S4Q batteries exhibit satisfactory electrochemical performance based on 3.5 mol L-1(M)Zn(ClO4)2electrolyte.For instance,the Zn//4S6Q battery obtains 240 and 208.6 mAh g^(-1)of discharge capacity at 150 mA g^(-1)and 30 A g^(-1),respectively.The excellent rate capability is ascribed to the fast reaction kinetics.This system displays a superlong life of 20,000 cycles with no capacity fading at 3 A g^(-1).Additionally,the H+-storage mechanism of the 4S6Q compound is demonstrated by ex situ analyses and density functional theory calculations.Impressively,the battery can normally work at-60℃benefiting from the anti-freezing electrolyte and maintain a high discharge capacity of 201.7 mAh g^(-1),which is 86.2%of discharge capacity at 25℃.The cutting-edge electrochemical performances of these novel compounds make them alternative electrode materials for Zn-organic batteries.
