物理化学学报2025，Vol.41Issue(7)：65-74,10.DOI:10.1016/j.actphy.2025.100066
丝光沸石负载自支撑氮掺杂多孔碳纳米纤维电容器及高效选择性去除硬度离子
Efficient adsorption of hardness ions by a mordenite-loaded,nitrogen-doped porous carbon nanofiber cathode in capacitive deionization
摘要
Abstract
Water hardness,predominantly due to the presence of Ca2+and Mg2+ions,presents significant challenges to water quality and public health.Addressing this issue necessitates effective water softening,which remains a pivotal task in water treatment.Capacitive deionization(CDI)has emerged as a promising technology for selective hardness removal,leveraging the low-cost,non-toxic and environmentally friendly selective electrode materials.Electrospun nanofibers,characterized by their three-dimensional porous structure,offer good flexibility,high specific surface area and excellent electrical conductivity.Their components can be tailored to meet the specific requirements.In this study,we incorporated mordenite(MOR),noted for its excellent ion-exchange capacity,into self-supporting nitrogen-doped carbon nanofibers(N-CNF)via electrospinning a blend of polyacrylonitrile(PAN),urea,and MOR,followed by carbonization.The resulting mordenite-loaded N-CNF composite(MOR@N-CNF)exhibited good flexibility and high conductivity.Scanning electron microscopy and X-ray diffraction analysis confirmed the presence and uniform distribution of MOR within the CNF matrix.X-ray photo spectroscopy demonstrated an increase in nitrogen content in MOR@N-CNF.In addition,the MOR@N-CNF composite displayed enhanced hydrophilicity and an increased specific surface area.When used as a self-supporting electrode,MOR@N-CNF exhibited the electrochemical specific capacitance of 162.7 F∙g-1,with the specific capacitance retention of 60%in a CaCl2 solution.In an asymmetric CDI setup with activated carbon(AC)as the anode,the MOR@N-CNF cathode demonstrated outstanding adsorption capacities of 1501 and 1416 μmol∙g-1 for Mg2+and Ca2+,respectively.The composite electrode exhibited high selectivity for Mg2+and Ca2+over Na+with a selectivity factor of 9.7 and 8.9,respectively.These attributes endow the material with exceptional ability to discriminate between divalent and monovalent ions,thereby enhancing its potential for hardness removal.Furthermore,the electrode retained 78%of its adsorption capacity after 40 cycles,demonstrating robust cyclic stability,and ensuring long-term CDI operation.This work provides a new strategy for preparing ion-exchange material-based composite electrodes and highlights the potential of CDI technology in hard water softening.关键词
自支撑/碳纤维/电容去离子/选择性吸附/硬度离子Key words
Self-supporting/Carbon nanofiber/Capacitive deionization/Selective adsorption/Hardness ion分类
化学化工引用本文复制引用
黄鋆,聂鹏飞,鲁勇朝,李佳洋,王怡文,刘建允..丝光沸石负载自支撑氮掺杂多孔碳纳米纤维电容器及高效选择性去除硬度离子[J].物理化学学报,2025,41(7):65-74,10.基金项目
The project was supported by the National Natural Science Foundation of China(21776045)and the Natural Science Foundation of Shanghai(23ZR1401200).国家自然科学基金(21776045)和上海市自然科学基金(23ZR1401200)资助项目 （21776045）
