Covalent organic frameworks(COFs)exhibiting reversible redox behaviors have been identified as promising candidates for constructing electrode materials in lithium-ion batteries(LIBs).However,their extensive applicati...Covalent organic frameworks(COFs)exhibiting reversible redox behaviors have been identified as promising candidates for constructing electrode materials in lithium-ion batteries(LIBs).However,their extensive application has been limited due to finite redox sites and poor structural stability.In this study,we design and synthesize a novel polyimide covalent organic framework(PI-COF)using the traditional solvothermal method and successfully apply it as an anode material for LIBs.The large conjugated structure of PI-COF accelerates charge transfer,while its large surface area provides more active sites,making PI-COF an attractive anode material for LIBs.Furthermore,the PI-COF anode material demonstrates high reversible specific capacity and excellent long-term cycling stability due to its COF characteristics.Specifically,the PI-COF electrodes deliver a specific capacity of 800 m Ah/g at a current density of 200 m A/g after 200 cycles,while a specific capacity of 450 m Ah/g at a current density of 1000 m A/g is sustained after 800 cycles.The outstanding lithium storage capacity,particularly the satisfactory long-term cycling stability,establishes PI-COF as a promising material for LIBs.展开更多
In this work,we report a novel one-dimensional metal-organic framework(MOF)templated for the synthesis of transition metal sulfides with excellent oxygen evolution reaction(OER)performance via a self-sulfidation proce...In this work,we report a novel one-dimensional metal-organic framework(MOF)templated for the synthesis of transition metal sulfides with excellent oxygen evolution reaction(OER)performance via a self-sulfidation process,eliminating the need for additional sulfur sources.After pyrolysis,MOFs containing Co ions as the metal nodes and 1-phenyl-5-mercaptotetrazole(PMTA)as the ligand were transformed to Co_(9)S_(8)nanoparticles,which were encapsulated in a nitrogen and sulfur dual-doped carbon(Co_(9)S_(8)@NSC)matrix.Additionally,PMTA,as a ligand,possesses the unique advantage of forming porous coordination polymers with a wide range of metals(e.g.,Fe,Ni,and Cu),enabling the versatile synthesis of transition metal sulfide electrocatalysts.Consequently,when served as the electrocatalyst for OER,the N,S co-doped Co_(9)S_(8)@NSC porous nanotubes exhibited excellent OER performance with the overpotential of only 248 mV at 10 mA cm^(−2)and long-term stability.These works provide new insights and inspiration for the rational design and development of non-precious metal-based sulfides with practical potential applications.展开更多
基金supported by National Natural Science Foundation of China for Youths(Nos.21701059,22205084,51902140)Natural Science Foundation of Jiangsu Province for Youths(No.BK20170571)the financial support by Shandong Key Laboratory of Biochemical Analysis(No.SKLBA2103)。
文摘Covalent organic frameworks(COFs)exhibiting reversible redox behaviors have been identified as promising candidates for constructing electrode materials in lithium-ion batteries(LIBs).However,their extensive application has been limited due to finite redox sites and poor structural stability.In this study,we design and synthesize a novel polyimide covalent organic framework(PI-COF)using the traditional solvothermal method and successfully apply it as an anode material for LIBs.The large conjugated structure of PI-COF accelerates charge transfer,while its large surface area provides more active sites,making PI-COF an attractive anode material for LIBs.Furthermore,the PI-COF anode material demonstrates high reversible specific capacity and excellent long-term cycling stability due to its COF characteristics.Specifically,the PI-COF electrodes deliver a specific capacity of 800 m Ah/g at a current density of 200 m A/g after 200 cycles,while a specific capacity of 450 m Ah/g at a current density of 1000 m A/g is sustained after 800 cycles.The outstanding lithium storage capacity,particularly the satisfactory long-term cycling stability,establishes PI-COF as a promising material for LIBs.
基金supported by the National Natural Science Foundation of China(21701059,51902140 and 52102100)the Natural Science Foundation of Jiangsu Province for Youths(BK20170571).
文摘In this work,we report a novel one-dimensional metal-organic framework(MOF)templated for the synthesis of transition metal sulfides with excellent oxygen evolution reaction(OER)performance via a self-sulfidation process,eliminating the need for additional sulfur sources.After pyrolysis,MOFs containing Co ions as the metal nodes and 1-phenyl-5-mercaptotetrazole(PMTA)as the ligand were transformed to Co_(9)S_(8)nanoparticles,which were encapsulated in a nitrogen and sulfur dual-doped carbon(Co_(9)S_(8)@NSC)matrix.Additionally,PMTA,as a ligand,possesses the unique advantage of forming porous coordination polymers with a wide range of metals(e.g.,Fe,Ni,and Cu),enabling the versatile synthesis of transition metal sulfide electrocatalysts.Consequently,when served as the electrocatalyst for OER,the N,S co-doped Co_(9)S_(8)@NSC porous nanotubes exhibited excellent OER performance with the overpotential of only 248 mV at 10 mA cm^(−2)and long-term stability.These works provide new insights and inspiration for the rational design and development of non-precious metal-based sulfides with practical potential applications.
