封装包覆结构多孔Fe_(3)O_(4)长循环锂电池负极材料  

Encapsulated and coated porous Fe_(3)O_(4)materials as the long-cycle anode materials for lithium-ion batteries

作　　者：仇实 李瑞[1] 汪洋[1] 谢伟[1] 吴启超 QIU Shi;LI Rui;WANG Yang;XIE Wei;WU Qi-chao(College of Chemical Engineering,Yangzhou Polytechnic Institute,Yangzhou 225127,China)

机构地区：[1]扬州工业职业技术学院化学工程学院,江苏扬州225127

出　　处：《化学研究与应用》2024年第2期338-348,共11页Chemical Research and Application

基　　金：国家自然科学基金(51674262)资助;江苏省高等学校基础科学(自然科学)研究项目(21KJB480013)资助;扬州工业职业技术学院高水平项目(2023gsp002)资助。

摘　　要：本文通过封装与包覆结构共同作用抑制多级孔Fe_(3)O_(4)在循环过程中的体积膨胀,提高Fe_(3)O_(4)电极材料的电化学性能。通过采用硬模板法将葡萄糖和尿素作为造孔剂合成具有多级孔结构的Fe_(3)O_(4)材料,再利用醛脂包覆系统在多级孔Fe_(3)O_(4)上均匀的包覆一层碳材料,随后使用氢化工程对体积膨胀率仅为~4%的TiO_(2)进行氢化处理并提高TiO_(2)的导电率,将氢化TiO_(2)作为封装材料对碳包覆多级孔Fe_(3)O_(4)进行封装处理,制备出具有三维网络传输结构的H-TiO_(2)-C-Fe_(3)O_(4)电极材料。结果表明,封装与包覆结构较好的缓解了H-TiO_(2)-C-Fe_(3)O_(4)电极材料在充放电过程中的体积膨胀,在0.2 A·g^(-1)的电流密度下循环500圈之后的放电比容量为599.61 mAh·g^(-1),以1 A·g^(-1)的电流密度循环700圈后的比容量为542.64 mAh·g^(-1),即使在6 A·g^(-1)的大电流密度下比容量也能够达到168.7 mAh·g^(-1),当电流返回0.2 A·g^(-1)循环100圈后的比容量为671.91 mAh·g^(-1),优异的倍率性能为H-TiO_(2)-C-Fe_(3)O_(4)样品在大电流储能设备上使用提供了可能性。In this study,porous Fe_(3)O_(4)are employed as an anode electrode for lithium-ion batteries.Through the synergistic effect of encapsulation and coating,the volume expansion of this electrode during cycling is effectively suppressed,leading to improved elec-trochemical performance.The hard template method was utilized to prepare Fe_(3)O_(4)with hierarchical pore structure,using glucose and urea as pore-forming agents.We employed a formaldehyde resin system to uniformly coat a layer of carbonaceous materials on the surface of porous Fe_(3)O_(4).Subsequently,hydrogenation treatment was applied to TiO_(2)with the volume expansion rate of only~4%to enhance the electrical conductivity.As a result,we synthesized H-TiO_(2)-C-Fe_(3)O_(4)electrode with a three-dimensional network trans-mission structure,by using hydrogenated TiO_(2)to encapsulate the carbon-coated porous Fe_(3)O_(4).This research demonstrates that the encapsulation and coating structure effectively inhibit the volume expansion of H-TiO_(2)-C-Fe_(3)O_(4)electrode during the charge and dis-charge process.After 500 cycles at a current density of 0.2 A·g^(-1),the discharge specific capacity of H-TiO_(2)-C-Fe_(3)O_(4)electrode is measured to be 599.61 mAh·g^(-1).Furthermore,at a current density of 1 A·g^(-1),the discharge specific capacity is found to be 54264 mAh·g^(-1)after 700 cycles.At a high current density of 6 A·g^(-1),the specific capacity remains impressive at 168.7 mAh·g^(-1)The outstanding rate performance of H-TiO_(2)-C-Fe_(3)O_(4)electrode provides the possibility for its application in high-current energy storage devices.

关 键 词：Fe_(3)O_(4) 包覆 封装 锂离子电池 

分 类 号：O614[理学—无机化学]