With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of l...With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of lithiumion batteries(LIBs)can be attributed to their numerous advantages,including high energy density,high operating voltage,environmental friendliness,and lack of memory effect.However,the progress of LIBs is currently hindered by the limitations of energy storage materials,which serve as vital components.Therefore,there is an urgent need to address the development of a new generation of high-rate energy storage materials in order to overcome these limitations and further advance LIB technology.Niobium-based oxides have emerged as promising candidates for the fabrication of fast-charging Li-ion batteries due to their excellent rate capability and long lifespan.This review paper provides a comprehensive analysis of the fundamentals,methodologies,and electrochemistries of niobium-based oxides,with a specific focus on the evolution and creation of crystal phases of Nb_(2)O_(5),fundamental electrochemical behavior,and modification methods including morphology modulation,composite technology,and carbon coating.Furthermore,the review explores Nb_(2)O_(5)-derived compounds and related advanced characterization techniques.Finally,the challenges and issues in the development of niobiumbased oxides for high-rate energy storage batteries are discussed,along with future research perspectives.展开更多
Herein,a simple yet efficient hydrothermal strategy is developed to in-situ convert multi-layered niobium-based MXene(Nb2 CTx)to hierarchical Nb2 CTx/Nb2O5 composite.In the hybrid,the Nb2O5 nanorods are well dispersed...Herein,a simple yet efficient hydrothermal strategy is developed to in-situ convert multi-layered niobium-based MXene(Nb2 CTx)to hierarchical Nb2 CTx/Nb2O5 composite.In the hybrid,the Nb2O5 nanorods are well dispersed in and/or on the Nb2 CTx.Thanks to the synergetic contributions from the high capacity of Nb2O5 and superb electrical conductivity of the two-dimensional Nb2 CTx itself,the resultant Nb2 CTx/Nb2O5 hybrid exhibits excellent rate behaviors and stable long-term cycling behaviors,when evaluated as anodes for Li-ion batteries.展开更多
An effective method is designed to construct three-dimensional(3D)Nb_(2)C/reduced graphene oxide(rGO)hybrid aerogels through a low-temperature graphene oxide(GO)-assisted hydrothermal self-assembly followed by freeze-...An effective method is designed to construct three-dimensional(3D)Nb_(2)C/reduced graphene oxide(rGO)hybrid aerogels through a low-temperature graphene oxide(GO)-assisted hydrothermal self-assembly followed by freeze-drying and annealing.The intimately coupled Nb_(2)C/rGO hybrid aerogel combines the advantages of large specific surface area and rich 3D interconnected porous structure of aerogel as well as high conductivity and low potassium diffusion energy barrier of Nb_(2)C,which not only effectively prevents the self-restacking of Nb2C nanosheets to allow more active sites exposed and accommodate the volume change during the charge/discharge process,but also increases the accessibility of electrolyte and promotes the rapid transfer of ions/electrons.As a result,Nb_(2)C/rGO-2 as the anode of potassium ion batteries(KIBs)delivers a large reversible specific capacity(301.7 mAh·g^(−1)after 500 cycles at 2.0 A·g^(−1)),an ultrahigh rate capability(155.5 mAh·g^(−1)at 20 A·g^(−1)),and an excellent long-term large-current cycle stability(198.8 mAh·g^(−1)after 1,000 cycles at 10 A·g^(−1),with a retention of 83.3%).Such a high-level electrochemical performance,especially the ultrahigh rate capability,is the best among transition metal carbides and nitride(MXene)-based materials reported so far for KIBs.The diffusion kinetics of K+is investigated thoroughly,and the synergetic charge–discharge mechanism and the structure–performance relationship of Nb_(2)C/rGO are revealed explicitly.The present work provides a good strategy to solve the self-restacking problem of two-dimensional materials and also enlarges the potential applications of MXenes.展开更多
基金This work was financially supported by“Hundred Young Talents Program”(No.263113491)from Guangdong University of Technology.
文摘With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of lithiumion batteries(LIBs)can be attributed to their numerous advantages,including high energy density,high operating voltage,environmental friendliness,and lack of memory effect.However,the progress of LIBs is currently hindered by the limitations of energy storage materials,which serve as vital components.Therefore,there is an urgent need to address the development of a new generation of high-rate energy storage materials in order to overcome these limitations and further advance LIB technology.Niobium-based oxides have emerged as promising candidates for the fabrication of fast-charging Li-ion batteries due to their excellent rate capability and long lifespan.This review paper provides a comprehensive analysis of the fundamentals,methodologies,and electrochemistries of niobium-based oxides,with a specific focus on the evolution and creation of crystal phases of Nb_(2)O_(5),fundamental electrochemical behavior,and modification methods including morphology modulation,composite technology,and carbon coating.Furthermore,the review explores Nb_(2)O_(5)-derived compounds and related advanced characterization techniques.Finally,the challenges and issues in the development of niobiumbased oxides for high-rate energy storage batteries are discussed,along with future research perspectives.
基金the financial support from the National Natural Science Foundation of China(Nos.51772127 and 51772131)Taishan Scholars(No.ts201712050)+3 种基金Major Program of Shandong Province Natural Science Foundation(No.ZR2018ZB0317)Natural Science Doctoral Foundation of Shandong Province(No.ZR2019BEM038)Natural Science Doctoral Foundation of the University of Jinan(No.XBS1830)Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong。
文摘Herein,a simple yet efficient hydrothermal strategy is developed to in-situ convert multi-layered niobium-based MXene(Nb2 CTx)to hierarchical Nb2 CTx/Nb2O5 composite.In the hybrid,the Nb2O5 nanorods are well dispersed in and/or on the Nb2 CTx.Thanks to the synergetic contributions from the high capacity of Nb2O5 and superb electrical conductivity of the two-dimensional Nb2 CTx itself,the resultant Nb2 CTx/Nb2O5 hybrid exhibits excellent rate behaviors and stable long-term cycling behaviors,when evaluated as anodes for Li-ion batteries.
基金the National Natural Science Foundation of China(No.21773116)and Modern Analysis Center of Nanjing University.
文摘An effective method is designed to construct three-dimensional(3D)Nb_(2)C/reduced graphene oxide(rGO)hybrid aerogels through a low-temperature graphene oxide(GO)-assisted hydrothermal self-assembly followed by freeze-drying and annealing.The intimately coupled Nb_(2)C/rGO hybrid aerogel combines the advantages of large specific surface area and rich 3D interconnected porous structure of aerogel as well as high conductivity and low potassium diffusion energy barrier of Nb_(2)C,which not only effectively prevents the self-restacking of Nb2C nanosheets to allow more active sites exposed and accommodate the volume change during the charge/discharge process,but also increases the accessibility of electrolyte and promotes the rapid transfer of ions/electrons.As a result,Nb_(2)C/rGO-2 as the anode of potassium ion batteries(KIBs)delivers a large reversible specific capacity(301.7 mAh·g^(−1)after 500 cycles at 2.0 A·g^(−1)),an ultrahigh rate capability(155.5 mAh·g^(−1)at 20 A·g^(−1)),and an excellent long-term large-current cycle stability(198.8 mAh·g^(−1)after 1,000 cycles at 10 A·g^(−1),with a retention of 83.3%).Such a high-level electrochemical performance,especially the ultrahigh rate capability,is the best among transition metal carbides and nitride(MXene)-based materials reported so far for KIBs.The diffusion kinetics of K+is investigated thoroughly,and the synergetic charge–discharge mechanism and the structure–performance relationship of Nb_(2)C/rGO are revealed explicitly.The present work provides a good strategy to solve the self-restacking problem of two-dimensional materials and also enlarges the potential applications of MXenes.
