Aluminum^-graphene battery is promising for its abundant raw materials,high power density,ultralong cycle life and superior safety.However,the development of aluminum^-graphene battery is currently restricted by its i...Aluminum^-graphene battery is promising for its abundant raw materials,high power density,ultralong cycle life and superior safety.However,the development of aluminum^-graphene battery is currently restricted by its insufficient cathode capacity,calling for a newly developed working mechanism.In addition,an irregular constant increase of the cathode capacity was always observed during cycling,but cannot be explained based on the current understanding.Here,we observed an increase of specific capacity by 60%with stable Coulombic efficiency of 98%during 7000 cycles life of Al-graphene batteries employing AlCl3/ET3NHCl electrolyte.We demonstrated this growing cathode capacity is attributed to an increasing contribution of capacitive charge storage during cycling,because a gradually enlarged surface area as capacitive active sites is enabled by the exfoliation of graphitic cathode during the periodic intercalation process.Moreover,the graphene cathode was exfoliated more significantly in AlCl3/ET3NHCl than 1-ethyl-3-methylimidazolium chloride-based electrolyte,which results from the heavier stress on the graphene layers caused by the larger intercalants in AlCl3/ET3NHCl.The common intercalation of cations with AlCl4-clusters was therefore supposed to occur during charging.This new proposed mechanism can offer the new thought for future design on high-capacity cathode of Al-ion battery.展开更多
The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different ...The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different from usual polymers and metals,graphene solids exhibit limited deformability and processibility for precise forming.Here,we present a precise thermoplastic forming of graphene materials by polymer intercalation from graphene oxide(GO)precursor.The intercalated polymer enables the thermoplasticity of GO solids by thermally activated motion of polymer chains.We detect a critical minimum containing of intercalated polymer that can expand the interlayer spacing exceeding 1.4 nm to activate thermoplasticity,which becomes the criteria for thermal plastic forming of GO solids.By thermoplastic forming,the flat GO-composite films are forged to Gaussian curved shapes and imprinted to have surface relief patterns with size precision down to 360 nm.The plastic-formed structures maintain the structural integration with outstanding electrical(3.07×10^(5) S m^(−1))and thermal conductivity(745.65 W m^(−1) K^(−1))after removal of polymers.The thermoplastic strategy greatly extends the forming capability of GO materials and other layered materials and promises versatile structural designs for more broad applications.展开更多
Carbon-based microassemblies(CMs) have attracted significant attention in numerous applications due to their unique hierarchical structures and delicate building blocks,especially when hollow carbon spheres(HCSs) are ...Carbon-based microassemblies(CMs) have attracted significant attention in numerous applications due to their unique hierarchical structures and delicate building blocks,especially when hollow carbon spheres(HCSs) are reasonably introduced into the construction.Herein,a new design for novel HCSscombined CMs is proposed.Remarkably,the HCSs are linear carbon bubbles linked one-by-one, arranging into necklaces decorating on the graphene microfolds.Detailed thermal analysis confirm that high temperatures straighten the linked carbon bubbles into bamboo-like carbon nanofibers,evidently due to the attenuation of doping degree.Benefiting from the abundant active sites of carbon bubbles,the obtained CMs exhibit satisfactory electrocatalytic activity for oxygen reduction reactions.This work establishes a bridge to precisely control the synthesis of carbon-based hierarchical architectures.展开更多
Aluminum-ion battery(AIB)is very promising for its safety and large current charge–discharge.However,it is challenging to build a high-performance AIB system based on low-cost materials especially cathode&electro...Aluminum-ion battery(AIB)is very promising for its safety and large current charge–discharge.However,it is challenging to build a high-performance AIB system based on low-cost materials especially cathode&electrolyte.Despite the low-cost expanded graphite-triethylaminehydrochloride(EG-ET)system has been improved in cycle performance,its rate capability still remains a gap with the expensive graphene-alkylimidazoliumchloride AIB system.In this work,we treated the cheap EG appropriately through an industrial high-temperature process,employed the obtained EG3K(treated at 3000℃)cathode with AlCl_(3)-ET electrolyte,and built a novel,high-rate capability and double-cheap AIB system.The new EG3K-ET system achieved the cathode capacity of average 110 m Ah g^(-1)at 1 A g^(-1)with 18,000cycles,and retained the cathode capacity of 100 m Ah g^(-1)at 5 A g^(-1)with 27,500 cycles(fast charging of 72 s).Impressively,we demonstrated that a battery pack(EG3K-ET system,12 m Ah)had successfully driven the Model car running 100 m long.In addition,it was confirmed that the improvement of rate capability in the EG3K-ET system was mainly derived by deposition,and its capacity contribution ratio was about 53.7%.This work further promoted the application potential of the low-cost EG-ET AIB system.展开更多
基金supported by the National Natural Science Foundation of China(No.51533008)National Key R&D Program of China(No.2016YFA0200200)+1 种基金Key Research and Development Plan of Zhejiang Province(2018C01049)Fujian Provincial Science and Technology Major Projects(No.2018HZ0001-2)。
文摘Aluminum^-graphene battery is promising for its abundant raw materials,high power density,ultralong cycle life and superior safety.However,the development of aluminum^-graphene battery is currently restricted by its insufficient cathode capacity,calling for a newly developed working mechanism.In addition,an irregular constant increase of the cathode capacity was always observed during cycling,but cannot be explained based on the current understanding.Here,we observed an increase of specific capacity by 60%with stable Coulombic efficiency of 98%during 7000 cycles life of Al-graphene batteries employing AlCl3/ET3NHCl electrolyte.We demonstrated this growing cathode capacity is attributed to an increasing contribution of capacitive charge storage during cycling,because a gradually enlarged surface area as capacitive active sites is enabled by the exfoliation of graphitic cathode during the periodic intercalation process.Moreover,the graphene cathode was exfoliated more significantly in AlCl3/ET3NHCl than 1-ethyl-3-methylimidazolium chloride-based electrolyte,which results from the heavier stress on the graphene layers caused by the larger intercalants in AlCl3/ET3NHCl.The common intercalation of cations with AlCl4-clusters was therefore supposed to occur during charging.This new proposed mechanism can offer the new thought for future design on high-capacity cathode of Al-ion battery.
基金the support of the National Natural Science Foundation of China(Nos.51803177,51973191,51533008,and 51636002)National Key R&D Program of China(No.2016YFA0200200)+5 种基金the China Postdoctoral Science Foundation(No.2021M690134)Hundred Talents Program of Zhejiang University(188020*194231701/113)Key Research and Development Plan of Zhejiang Province(2018C01049)the National Postdoctoral Program for Innovative Talents(No.BX201700209)the Fundamental Research Funds for the Central Universities(2021FZZX001-17),the Natural Science Foundation of Jiangsu Province(BK20210353)the Fundamental Research Funds for the Central Universities(No.30920041106).
文摘The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different from usual polymers and metals,graphene solids exhibit limited deformability and processibility for precise forming.Here,we present a precise thermoplastic forming of graphene materials by polymer intercalation from graphene oxide(GO)precursor.The intercalated polymer enables the thermoplasticity of GO solids by thermally activated motion of polymer chains.We detect a critical minimum containing of intercalated polymer that can expand the interlayer spacing exceeding 1.4 nm to activate thermoplasticity,which becomes the criteria for thermal plastic forming of GO solids.By thermoplastic forming,the flat GO-composite films are forged to Gaussian curved shapes and imprinted to have surface relief patterns with size precision down to 360 nm.The plastic-formed structures maintain the structural integration with outstanding electrical(3.07×10^(5) S m^(−1))and thermal conductivity(745.65 W m^(−1) K^(−1))after removal of polymers.The thermoplastic strategy greatly extends the forming capability of GO materials and other layered materials and promises versatile structural designs for more broad applications.
基金financially supported by the National Key R&D Program of China(2017YFA0207201)the National Natural Science Foundation of China(51872139,21905133,51902158)+4 种基金the NSF of Jiangsu Province(BK20170045)the Recruitment Program of Global Experts(1211019)the “Six Talent Peak”Project of Jiangsu Province(XCL-043)the Fundamental Research Funds for the Central Universities and the Recruitment Program of Global Experts(1211019,31020200QD041)the Jiangsu Province Postdoctoral Science Foundation(2019K191)。
文摘Carbon-based microassemblies(CMs) have attracted significant attention in numerous applications due to their unique hierarchical structures and delicate building blocks,especially when hollow carbon spheres(HCSs) are reasonably introduced into the construction.Herein,a new design for novel HCSscombined CMs is proposed.Remarkably,the HCSs are linear carbon bubbles linked one-by-one, arranging into necklaces decorating on the graphene microfolds.Detailed thermal analysis confirm that high temperatures straighten the linked carbon bubbles into bamboo-like carbon nanofibers,evidently due to the attenuation of doping degree.Benefiting from the abundant active sites of carbon bubbles,the obtained CMs exhibit satisfactory electrocatalytic activity for oxygen reduction reactions.This work establishes a bridge to precisely control the synthesis of carbon-based hierarchical architectures.
基金the support of the National Natural Science Foundation of China(51533008,51703194 and 21805242)the National Key R&D Program of China(2016YFA0200200)the Excellent Postdoctoral Special Fund of Zhejiang University for funding this research work。
文摘Aluminum-ion battery(AIB)is very promising for its safety and large current charge–discharge.However,it is challenging to build a high-performance AIB system based on low-cost materials especially cathode&electrolyte.Despite the low-cost expanded graphite-triethylaminehydrochloride(EG-ET)system has been improved in cycle performance,its rate capability still remains a gap with the expensive graphene-alkylimidazoliumchloride AIB system.In this work,we treated the cheap EG appropriately through an industrial high-temperature process,employed the obtained EG3K(treated at 3000℃)cathode with AlCl_(3)-ET electrolyte,and built a novel,high-rate capability and double-cheap AIB system.The new EG3K-ET system achieved the cathode capacity of average 110 m Ah g^(-1)at 1 A g^(-1)with 18,000cycles,and retained the cathode capacity of 100 m Ah g^(-1)at 5 A g^(-1)with 27,500 cycles(fast charging of 72 s).Impressively,we demonstrated that a battery pack(EG3K-ET system,12 m Ah)had successfully driven the Model car running 100 m long.In addition,it was confirmed that the improvement of rate capability in the EG3K-ET system was mainly derived by deposition,and its capacity contribution ratio was about 53.7%.This work further promoted the application potential of the low-cost EG-ET AIB system.