Niobium-based oxides show great potential in anode materials for fast-charging lithium-ion batteries,but their practical application remains hindered by intrinsically low conductivity.In this study,we successfully syn...Niobium-based oxides show great potential in anode materials for fast-charging lithium-ion batteries,but their practical application remains hindered by intrinsically low conductivity.In this study,we successfully synthesize nano-sized Wadsley-Roth FeNb_(11)O_(29)through Fe-driven phase transformation of Nb_(2)O_(5),which delivers a high specific capacity(280.5 mA h g^(−1)at 0.25 C)along with abundant redox-active sites.Moreover,the Wadsley-Roth shear structure of FeNb_(11)O_(29)facilitates rapid Li^(+)diffusion and guarantees exceptional structural stability.Theoretical calculations further confirm that FeNb_(11)O_(29)has a narrow band gap,which significantly enhances the conductivity.Owing to these merits,FeNb_(11)O_(29)achieves a full charge/discharge cycle within merely 25 s at 75 C rate and retains remarkable cycling stability over 2500 cycles.As a consequence,our assembled FeNb_(11)O_(29)||LiFePO_(4)full cell demonstrates ultra-long cyclability(>10000 cycles)and outstanding fast-charging capability(complete cycling within 2 min at 30 C).These findings highlight nano-sized FeNb_(11)O_(29)as a highly promising anode candidate for next-generation fast-charging LIBs.展开更多
Wadsley-Roth (W-R) structured oxides featured with wide channels represent one of the most promising material families showing compelling rate performance for lithium-ion batteries.Herein,we report an indepth study on...Wadsley-Roth (W-R) structured oxides featured with wide channels represent one of the most promising material families showing compelling rate performance for lithium-ion batteries.Herein,we report an indepth study on the fast and extensive intercalation chemistry of phosphorus stabilized W-R phase PNb_(9)O_(25) and its application in high energy and fast-charging devices.We explore the intercalation geometry of PNb_(9)O_(25) and identify two geometrical types of stable insertion sites with the total amount much higher than conventional intercalation-type electrodes.We reveal the ion transportation kinetics that the Li ions initially diffuse along the open type Ⅲ channels and then penetrate to edge sites with low kinetic barriers.During the lithiation,no remarkable phase transition is detected with nearly intact host phosphorous niobium oxide backbone.Therefore,the oxide framework of PNb_(9)O_(25) keeps almost unchanged with all the fast diffusion channels and insertion cavities well-maintained upon cycling,which accomplishes the unconventional electrochemical performance of W-R structured electrodes.展开更多
基金financially supported by the National Natural Science Foundation of China(52272209).Dedicated to his Alma Mater,Tianjin University,on the occasion of her 130th anniversary by Wei Zhang,who earned his bachelor's degree there in 1997.
文摘Niobium-based oxides show great potential in anode materials for fast-charging lithium-ion batteries,but their practical application remains hindered by intrinsically low conductivity.In this study,we successfully synthesize nano-sized Wadsley-Roth FeNb_(11)O_(29)through Fe-driven phase transformation of Nb_(2)O_(5),which delivers a high specific capacity(280.5 mA h g^(−1)at 0.25 C)along with abundant redox-active sites.Moreover,the Wadsley-Roth shear structure of FeNb_(11)O_(29)facilitates rapid Li^(+)diffusion and guarantees exceptional structural stability.Theoretical calculations further confirm that FeNb_(11)O_(29)has a narrow band gap,which significantly enhances the conductivity.Owing to these merits,FeNb_(11)O_(29)achieves a full charge/discharge cycle within merely 25 s at 75 C rate and retains remarkable cycling stability over 2500 cycles.As a consequence,our assembled FeNb_(11)O_(29)||LiFePO_(4)full cell demonstrates ultra-long cyclability(>10000 cycles)and outstanding fast-charging capability(complete cycling within 2 min at 30 C).These findings highlight nano-sized FeNb_(11)O_(29)as a highly promising anode candidate for next-generation fast-charging LIBs.
基金supported by the National Natural Science Foundation of China (51774251)the Hebei Natural Science Foundation for Distinguished Young Scholars (B2017203313)+7 种基金the Hundred Excellent Innovative Talents Support Program in Hebei Province (SLRC2017057)the Scientific Research Foundation for the Returned Overseas Chinese Scholars (CG2014003002)the Canada Foundation for Innovationthe Government of OntarioOntario Research Fund - Research Excellencethe University of Torontosupported by the National Natural Science Foundation of China (51702207 and 11972219)the Program for Professor of Special Appointment (Young Eastern Scholar Program) at Shanghai Institutions of Higher Learning。
文摘Wadsley-Roth (W-R) structured oxides featured with wide channels represent one of the most promising material families showing compelling rate performance for lithium-ion batteries.Herein,we report an indepth study on the fast and extensive intercalation chemistry of phosphorus stabilized W-R phase PNb_(9)O_(25) and its application in high energy and fast-charging devices.We explore the intercalation geometry of PNb_(9)O_(25) and identify two geometrical types of stable insertion sites with the total amount much higher than conventional intercalation-type electrodes.We reveal the ion transportation kinetics that the Li ions initially diffuse along the open type Ⅲ channels and then penetrate to edge sites with low kinetic barriers.During the lithiation,no remarkable phase transition is detected with nearly intact host phosphorous niobium oxide backbone.Therefore,the oxide framework of PNb_(9)O_(25) keeps almost unchanged with all the fast diffusion channels and insertion cavities well-maintained upon cycling,which accomplishes the unconventional electrochemical performance of W-R structured electrodes.
