陶瓷学报2025，Vol.46Issue(5)：926-933,8.DOI:10.13957/j.cnki.tcxb.2025.05.006
Cr2AlB2刻蚀及电化学性能研究
Study on Etching and Electrochemical Properties of Cr2AlB2
摘要
Abstract
[Background and purposes]The development of advanced anode materials for lithium-ion batteries(LIBs)is critical to meet the growing demand for high-energy-density and long-cycle-life energy storage systems.Among various emerging materials,MBenes,two-dimensional(2D)derivatives of ternary layered MAB phases,have drawn significant attention,due to their metallic conductivity,tunable surface chemistry and structural flexibility.Cr2AlB2,a representative MAB phase,holds promise for synthesizing 2D-CrB(a type of MBene)through selective etching of the Al layer.However,challenges persist in optimizing etching parameters,understanding the structural evolution and validating the electrochemical performance of 2D-CrB.Previous studies were primarily focused on theoretical predictions or preliminary synthesis,leaving gaps in systematic experimental validation and mechanistic insights.This study was aimed to establish a controllable HCl etching protocol for Cr2AlB2 to produce high-purity 2D-CrB and elucidate the structural advantages of the 2D architecture in enhancing lithium storage performance. [Methods]The Al layer in Cr2AlB2 was selectively etched using a wet chemical approach with HCl.Key parameters,including HCl concentration,temperature and etching duration,were systematically optimized.Structural and morphological evolution of the etched products was characterized by using X-ray diffraction(XRD),scanning electron microscopy(SEM)and Brunauer-Emmett-Teller(BET)surface area analysis.Electrochemical evaluations were conducted by assembling CR2032 coin cells with 2D-CrB or Cr2AlB2 as the working electrode,lithium foil as the counter/reference electrode and 1 M LiPF6 in EC/DMC/EMC(1:1:1 v/v)as the electrolyte.Cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS)and galvanostatic charge-discharge tests at various rates(0.1-1.6 C)were performed to assess lithium storage behavior. [Results]Optimal etching conditions(3 mol·L-1 HCl,20℃,6 h)enabled efficient Al layer removal,yielding 2D-CrB with a porous multilayered structure.XRD results confirmed the complete disappearance of Cr2AlB2 peaks and the formation of 2D-CrB as the dominant phase.SEM results revealed a transition from dense lamellar Cr2AlB2 to exfoliated 2D nanosheets with uniform thickness and exposed edges.BET analysis demonstrated a 12-fold increase in specific surface area(from 14.77 to 183.02 cm3·g-1)and a broader pore size distribution centered at 3 nm,facilitating electrolyte infiltration and ion diffusion.Electrochemically,2D-CrB outperformed Cr2AlB2 with an initial discharge capacity of 347.1 mAh·g-1 at 0.1 C,retaining 65.4%capacity after 100 cycles.At 0.2 C,2D-CrB maintained a stable capacity of 157 mAh·g-1 over 100 cycles,with Coulombic efficiency>98%,while Cr2AlB2 exhibited rapid decay to 59 mAh·g-1.EIS and CV analyses suggested this enhancement to reduced charge transfer resistance,improved Li+diffusion kinetics and effective buffering of volume strain owing to the 2D porous framework. [Conclusions]Controlled HCl etching enabled transformation of Cr2AlB2 into high-performance 2D-CrB with tailored porosity and enhanced electrochemical properties.The optimized 2D structure exhibited abundant active sites,rapid ion transport pathways and mechanical resilience against cycling-induced stress,thus addressing the critical limitations of bulk MAB phases.The findings validate 2D-CrB as a promising anode candidate for LIBs and offer a scalable synthesis strategy for MBene materials.Furthermore,the mechanistic insights into structure-property relationships paved a way for designing advanced 2D materials for energy storage applications.关键词
Cr2AlB2/2D-CrB/二维材料/刻蚀/锂离子电池/负极材料Key words
Cr2AlB2/2D-CrB/two-dimensional materials/etching/lithium-ion batteries/anode materials分类
化学化工引用本文复制引用
周雅宣,陈浩宇,邓玉宵,闫转龙,刘娅,严明..Cr2AlB2刻蚀及电化学性能研究[J].陶瓷学报,2025,46(5):926-933,8.基金项目
湖北省大学生创新创业训练计划项目(20250100007) （20250100007）
绿色轻工材料湖北省重点实验室开放基金(202509B13). （202509B13）
