Constructing heterojunctions and hollow multi-shelled structures can render materials with fascinating physicochemical properties,and have been regarded as two promising strategies to overcome the severe shuttling and...Constructing heterojunctions and hollow multi-shelled structures can render materials with fascinating physicochemical properties,and have been regarded as two promising strategies to overcome the severe shuttling and sluggish kinetics of polysulfide in lithium-sulfur(Li-S)batteries.However,a single strategy can only take limited effect.Modulating catalytic hosts with synergistic effects are urgently desired.Herein,Mn_(3)O_(4)-MnS heterogeneous multi-shelled hollow spheres are meticulously designed by controlled sulfuration of Mn2O3 hollow spheres,and then applied as advanced encapsulation hosts for Li-S batteries.Benefiting from the separated spatial confinement by hollow multi-shelled structure,ample exposed active sites and built-in electric field by heterogeneous interface,and synergistic effects between Mn_(3)O_(4)(strong adsorption)and MnS(fast conversion)components,the assembled battery achieves prominent rate capability and decent cyclability(0.016%decay per cycle at 2 C,1000 cycles).More crucially,satisfactory areal capacity reaches up to 7.1 mAh cm^(-2)even with high sulfur loading(8.0 mg cm^(-2))and lean electrolyte(E/S=4.0 pL mg^(-1))conditions.This work will provide inspiration for the rational design of hollow multi-shelled heterostructure for various electrocatalysis applications.展开更多
Because of their large volume variation and inferior electrical conductivity,Mn_(3)O_(4)-based oxide anode materials have short cyclic lives and poor rate capability,which obstructs their development.In this study,we ...Because of their large volume variation and inferior electrical conductivity,Mn_(3)O_(4)-based oxide anode materials have short cyclic lives and poor rate capability,which obstructs their development.In this study,we successfully prepared a Mn_(3)O_(4)/N-doped honeycomb carbon composite using a smart and facile synthetic method.The Mn_(3)O_(4)nanopolyhedra are grown on N-doped honeycomb carbon,which evidently mitigates the volume change in the charging and discharging processes but also improves the electrochemical reaction kinetics.More importantly,the Mn-O-C bond in the Mn_(3)O_(4)/N-doped honeycomb carbon composite benefits electrochemical reversibility.These features of the Mn_(3)O_(4)/N-doped honeycomb carbon(NHC)composite are responsible for its superior electrochemical performance.When used for Li-ion batteries,the Mn_(3)O_(4)/N-doped honeycomb carbon anode exhibits a high reversible capacity of 598 mAh·g^(−1)after 350 cycles at 1 A·g^(−1).Even at 2 A·g^(−1),the Mn_(3)O_(4)/NHC anode still delivers a high capacity of 472 mAh·g^(−1).This work provides a new prospect for synthesizing and developing manganese-based oxide materials for energy storage.展开更多
Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivit...Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivity and large volume expansion during Li^(+)intercalation.Herein,we designed and constructed a structurally integrated 3D carbon tube(3D-CT)grid film with Mn_(3)O_(4)nanoparticles(Mn_(3)O_(4)-NPs)and carbon nanotubes(CNTs)filled in the inner cavity of CTs(denoted as Mn_(3)O_(4)-NPs/CNTs@3D-CT)as high-performance free-standing anode for LIBs.The Mn_(3)O_(4)-NPs/CNTs@3D-CT grid with Mn_(3)O_(4)-NPs filled in the inner cavity of 3D-CT not only afford sufficient space to overcome the damage caused by the volume expansion of Mn_(3)O_(4)-NPs during charge and discharge processes,but also achieves highly efficient channels for the fast transport of both electrons and Li+during cycling,thus offering outstanding electrochemical performance(865 mAh g^(-1)at 1 A g^(-1)after 300 cycles)and excellent rate capability(418 mAh g^(-1)at 4 A g^(-1))based on the total mass of electrode.The unique 3D-CT framework structure would open up a new route to the highly stable,high-capacity,and excellent cycle and high-rate performance free-standing electrodes for highperformance Li-ion storage.展开更多
基金The support from the National Natural Science Foundation of China(No.51971083)the Natural Science Foundation of Heilongjiang Province,China(YQ 2020E007)is gratefully acknowledgedfinancially sponsored by Heilongjiang Touyan Team Program.
文摘Constructing heterojunctions and hollow multi-shelled structures can render materials with fascinating physicochemical properties,and have been regarded as two promising strategies to overcome the severe shuttling and sluggish kinetics of polysulfide in lithium-sulfur(Li-S)batteries.However,a single strategy can only take limited effect.Modulating catalytic hosts with synergistic effects are urgently desired.Herein,Mn_(3)O_(4)-MnS heterogeneous multi-shelled hollow spheres are meticulously designed by controlled sulfuration of Mn2O3 hollow spheres,and then applied as advanced encapsulation hosts for Li-S batteries.Benefiting from the separated spatial confinement by hollow multi-shelled structure,ample exposed active sites and built-in electric field by heterogeneous interface,and synergistic effects between Mn_(3)O_(4)(strong adsorption)and MnS(fast conversion)components,the assembled battery achieves prominent rate capability and decent cyclability(0.016%decay per cycle at 2 C,1000 cycles).More crucially,satisfactory areal capacity reaches up to 7.1 mAh cm^(-2)even with high sulfur loading(8.0 mg cm^(-2))and lean electrolyte(E/S=4.0 pL mg^(-1))conditions.This work will provide inspiration for the rational design of hollow multi-shelled heterostructure for various electrocatalysis applications.
基金financially supported by the Natural Science Foundation of Henan Province of China(No.222300420252)Nanyang Normal University(Nos.2020ZX013 and 2020ZX014).
文摘Because of their large volume variation and inferior electrical conductivity,Mn_(3)O_(4)-based oxide anode materials have short cyclic lives and poor rate capability,which obstructs their development.In this study,we successfully prepared a Mn_(3)O_(4)/N-doped honeycomb carbon composite using a smart and facile synthetic method.The Mn_(3)O_(4)nanopolyhedra are grown on N-doped honeycomb carbon,which evidently mitigates the volume change in the charging and discharging processes but also improves the electrochemical reaction kinetics.More importantly,the Mn-O-C bond in the Mn_(3)O_(4)/N-doped honeycomb carbon composite benefits electrochemical reversibility.These features of the Mn_(3)O_(4)/N-doped honeycomb carbon(NHC)composite are responsible for its superior electrochemical performance.When used for Li-ion batteries,the Mn_(3)O_(4)/N-doped honeycomb carbon anode exhibits a high reversible capacity of 598 mAh·g^(−1)after 350 cycles at 1 A·g^(−1).Even at 2 A·g^(−1),the Mn_(3)O_(4)/NHC anode still delivers a high capacity of 472 mAh·g^(−1).This work provides a new prospect for synthesizing and developing manganese-based oxide materials for energy storage.
基金supported by the Natural Science Foundation of China(91963202 and 52072372)the Key Research Program of Frontier Sciences(CAS,Grant,QYZDJ-SSW-SLH046)the CAS/SAFEA International Partnership Program for Creative Research Teams,and the Hefei Institutes of Physical Science,Chinese Academy of Sciences Director’s Fund(YZJ ZX202018)
文摘Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivity and large volume expansion during Li^(+)intercalation.Herein,we designed and constructed a structurally integrated 3D carbon tube(3D-CT)grid film with Mn_(3)O_(4)nanoparticles(Mn_(3)O_(4)-NPs)and carbon nanotubes(CNTs)filled in the inner cavity of CTs(denoted as Mn_(3)O_(4)-NPs/CNTs@3D-CT)as high-performance free-standing anode for LIBs.The Mn_(3)O_(4)-NPs/CNTs@3D-CT grid with Mn_(3)O_(4)-NPs filled in the inner cavity of 3D-CT not only afford sufficient space to overcome the damage caused by the volume expansion of Mn_(3)O_(4)-NPs during charge and discharge processes,but also achieves highly efficient channels for the fast transport of both electrons and Li+during cycling,thus offering outstanding electrochemical performance(865 mAh g^(-1)at 1 A g^(-1)after 300 cycles)and excellent rate capability(418 mAh g^(-1)at 4 A g^(-1))based on the total mass of electrode.The unique 3D-CT framework structure would open up a new route to the highly stable,high-capacity,and excellent cycle and high-rate performance free-standing electrodes for highperformance Li-ion storage.
