The state-of-the-art lithium-ion capacitors (LICs),consisting of high-capacity battery-type anode and high-rate capacitor-type cathode,can deliver high energy density and large power density when comparing with tradit...The state-of-the-art lithium-ion capacitors (LICs),consisting of high-capacity battery-type anode and high-rate capacitor-type cathode,can deliver high energy density and large power density when comparing with traditional supercapacitors and lithium-ion batteries,respectively.However,the ion kinetics mismatch between cathode and anode leads to unsatisfied cycling lifetime and anode degradation.Tremendous efforts have been devoted to solving the abovementioned issue.One promising strategy is altering high conductive hard carbon anode with excellent structural stability to match with activated carbon cathode,assembling dual-carbon LIC.In this contribution,one-pot in-situ expansion and heteroatom doping strategy was adopted to prepare sheet-like hard carbon,while activated carbon was obtained involving activation.Ammonium persulfate was used as expanding and doping agent simultaneously.While furfural residues (FR) were served as carbon precursor.The resulting hard carbon (FRNS-HC) and activated carbon (FRNS-AC)show excellent electrochemical performance as negative and positive electrodes in a lithium-ion battery (LIB).To be specific,374.2 m Ah g^(-1)and 123.1 m Ah g^(-1)can be achieved at 0.1 A g^(-1)and 5 A g^(-1)when FRNS-HC was tested as anode.When combined with a highly porous carbon cathode (S_(BET)=2961 m^(2)g^(-1)) synthesized from the same precursor,the LIC showed high specific energy of147.67 Wh kg^(-1)at approximately 199.93 W kg^(-1),and outstanding cycling life with negligible capacitance fading over 1000 cycles.This study could lead the way for the development of heteroatom-doped porous carbon nanomaterials applied to Li-based energy storage applications.展开更多
Sustainable development based on the value-added utilization of furfural residues(FRs)is an effective way to achieve a profitable circular economy.This comprehensive work highlights the potential of FRs as precursor t...Sustainable development based on the value-added utilization of furfural residues(FRs)is an effective way to achieve a profitable circular economy.This comprehensive work highlights the potential of FRs as precursor to prepare porous carbons for high performance supercapacitors(SCs).To improve the electrochemical performance of FR-based carbon materials,a facile route based on methanol pretreatment coupled with pre-carbonization and followed KOH activation is proposed.More defects could be obtained after methanol treatment,which is incline to optimize textural structure.The activated methanol treated FR-based carbon materials(AFRMs)possess high specific surface area(1753.5 m^(2) g^(-1)),large pore volume(0.85 cm^(3) g^(-1)),interconnected micro/mesoporous structure,which endow the AFRMs with good electrochemical performance in half-cell(326.1 F g^(-1) at 0.1 Ag^(-1),189.4 Fg^(-1) at 50 A g^(-1) in 6 mol L^(-1) KOH).The constructed symmetric SCs based on KOH,KOH–K_(3)Fe(CN)_(6) and KOH-KI electrolyte deliver energy density up to 8.9,9.9 and 10.6 Wh kg^(-1) with a capacitance retention of over 86%after 10,000 cycles.Furthermore,the self-discharge can be restrained by the addition of K_(3)Fe(CN)_(6) and KI in KOH electrolyte.This study provides an effective approach for high-valued utilization of FR waste.展开更多
基金financially supported by the National Natural Science Foundation of China (22075308, 22209197)Natural Science Foundation of Shanxi Province (20210302 1224439, 202203021211002)Shanxi Province Science Foundation for Youths (No: SQ2019001)。
文摘The state-of-the-art lithium-ion capacitors (LICs),consisting of high-capacity battery-type anode and high-rate capacitor-type cathode,can deliver high energy density and large power density when comparing with traditional supercapacitors and lithium-ion batteries,respectively.However,the ion kinetics mismatch between cathode and anode leads to unsatisfied cycling lifetime and anode degradation.Tremendous efforts have been devoted to solving the abovementioned issue.One promising strategy is altering high conductive hard carbon anode with excellent structural stability to match with activated carbon cathode,assembling dual-carbon LIC.In this contribution,one-pot in-situ expansion and heteroatom doping strategy was adopted to prepare sheet-like hard carbon,while activated carbon was obtained involving activation.Ammonium persulfate was used as expanding and doping agent simultaneously.While furfural residues (FR) were served as carbon precursor.The resulting hard carbon (FRNS-HC) and activated carbon (FRNS-AC)show excellent electrochemical performance as negative and positive electrodes in a lithium-ion battery (LIB).To be specific,374.2 m Ah g^(-1)and 123.1 m Ah g^(-1)can be achieved at 0.1 A g^(-1)and 5 A g^(-1)when FRNS-HC was tested as anode.When combined with a highly porous carbon cathode (S_(BET)=2961 m^(2)g^(-1)) synthesized from the same precursor,the LIC showed high specific energy of147.67 Wh kg^(-1)at approximately 199.93 W kg^(-1),and outstanding cycling life with negligible capacitance fading over 1000 cycles.This study could lead the way for the development of heteroatom-doped porous carbon nanomaterials applied to Li-based energy storage applications.
基金financially supported by the National Natural Science Foundation of China(22075308,U1710106,U1810111)Natural Science Foundation of Shanxi Province(No:201801D221371)Shanxi Province Science Foundation for Youths(No:SQ2019001).
文摘Sustainable development based on the value-added utilization of furfural residues(FRs)is an effective way to achieve a profitable circular economy.This comprehensive work highlights the potential of FRs as precursor to prepare porous carbons for high performance supercapacitors(SCs).To improve the electrochemical performance of FR-based carbon materials,a facile route based on methanol pretreatment coupled with pre-carbonization and followed KOH activation is proposed.More defects could be obtained after methanol treatment,which is incline to optimize textural structure.The activated methanol treated FR-based carbon materials(AFRMs)possess high specific surface area(1753.5 m^(2) g^(-1)),large pore volume(0.85 cm^(3) g^(-1)),interconnected micro/mesoporous structure,which endow the AFRMs with good electrochemical performance in half-cell(326.1 F g^(-1) at 0.1 Ag^(-1),189.4 Fg^(-1) at 50 A g^(-1) in 6 mol L^(-1) KOH).The constructed symmetric SCs based on KOH,KOH–K_(3)Fe(CN)_(6) and KOH-KI electrolyte deliver energy density up to 8.9,9.9 and 10.6 Wh kg^(-1) with a capacitance retention of over 86%after 10,000 cycles.Furthermore,the self-discharge can be restrained by the addition of K_(3)Fe(CN)_(6) and KI in KOH electrolyte.This study provides an effective approach for high-valued utilization of FR waste.
