物理化学学报2022，Vol.38Issue(6)：121-129,9.DOI:10.3866/PKU.WHXB202106002
镶嵌于NH2-MIL-125(Ti)衍生氮掺多孔碳中的花状超细纳米TiO2作为高活性和稳定性的锂离子电池负极材料
NH2-MIL-125(Ti)Derived Flower-Like Fine TiO2 Nanoparticles Implanted in N-doped Porous Carbon as an Anode with High Activity and Long Cycle Life for Lithium-Ion Batteries
摘要
Abstract
Owing to their advantages such as safe operation,high power density,long cycle life,and low self-discharge rate,lithium-ion batteries(LIBs)have attracted attention for applications ranging from portable electronics to electric vehicles(EVs)/hybrid EVs(HEVs).However,the striking exothermic reaction and growth of lithium dendrites during lithiation-delithiation cycles for commercial graphite anodes are hidden safety risks associated with LIBs.Titanium dioxide(TiO2)is considered as an important material for LIBs because of its high safety and excellent cycling stability.In addition,TiO2 anode used in lithium-ion storage system has a relatively high voltage(～1.5 V vs.Li/Li+),and thus,it meets the strict safety standards of commercial LIBs.However,the unsatisfactory conductivity and ion diffusion rate prevent the further application of TiO2 in LIBs.To date,the combination of graphene,carbon nanotubes(CNTs),carbon quantum dots(QDs)and porous carbon with TiO2 has attracted significant research attention.Nevertheless,it is still challenging to introduce a unique nanostructure design by organically compounding TiO2 with N-doped porous carbon matrix.Herein,N-doped porous carbon incorporating fine TiO2 nanoparticles(NPs)with a flower-like structure(denoted as FL-TiO2/NPC)is successfully prepared using flower-like NH2-MIL-125(Ti)as the hard template.The as-prepared Ti-based framework shows a flower-like structure,which is assembled with two-dimensional(2D)corrugated porous nanosheets.On the one hand,the corrugated carbon nanosheets incorporating fine TiO2 particles can offer a magnifying contact area between electrode matrix and electrolyte.On the other hand,the N-doped porous carbon plays a crucial role in improving the conductivity and structural integrity of the whole matrix.Therefore,the as-prepared FL-TiO2/NPC can deliver an excellent reversible lithium storage capacity of 384.2 mAh·g-1 at the current density of 0.5 A·g-1 after 300 cycles and 279.1 mAh·g-1 at 1 A·g-1 after 500 cycles.Furthermore,even when tested at 2 A·g-1,FL-TiO2/NPC can deliver a reversible capacity of 256.5 mAh·g-1 with a coulombic efficiency of 100％after 2000 cycles.The superior electrochemical performance and the structural toughness of LIBs originate from the unique flower-like structure.We believe that the proposed synthesis strategy will provide a new idea for the preparation of metal oxides/N-doped porous carbon composites with high lithium storage performance.关键词
纳米TiO2/氮掺杂多孔碳纳米片/花状结构/NH2-MIL-125(Ti)/负极/锂离子电池Key words
TiO2 nanoparticles/N-doped porous carbon nanosheet/Flower-like structure/NH2-MIL-125(Ti)/Anode/Lithium-ion battery分类
化学化工引用本文复制引用
杨越,朱加伟,王鹏彦,刘海咪,曾炜豪,陈磊,陈志祥,木士春..镶嵌于NH2-MIL-125(Ti)衍生氮掺多孔碳中的花状超细纳米TiO2作为高活性和稳定性的锂离子电池负极材料[J].物理化学学报,2022,38(6):121-129,9.基金项目
The project was supported by the National Key Research and Development Program of China(2016YFA0202603)and the National Natural Science Foundation of China(22075223).国家重点研发计划(2016YFA0202603)和国家自然科学基金(22075223)资助项目 （2016YFA0202603）
