煤沥青热解炭的制备及储钠性能研究  

Preparation of coal tar pitch pyrolytic carbon and its sodium storage properties

作　　者：陈林 张兆华 康伟伟 张亚飞[3] 张传祥 CHEN Lin;ZHANG Zhaohua;KANG Weiwei;ZHANG Yafei;ZHANG Chuanxiang(College of Chemistry and Chemical Engineering,Henan Polytechnic University,454003 Jiaozuo,China;Henan Key Laboratory of Coal Green Conversion,Henan Polytechnic University,454000 Jiaozuo,China;Ningbo Lüdong Fuel Cell Company Limited,315300 Ningbo,China;Collaborative Innovation Center of Coal Safety Production and Clean and Efficient Utilization Jointly Built by the Ministry and the Province,Henan Polytechnic University,454000 Jiaozuo,China)

机构地区：[1]河南理工大学化学化工学院,河南焦作454003 [2]河南理工大学河南省煤炭绿色转化重点实验室,河南焦作454000 [3]宁波绿动燃料电池有限公司,浙江宁波315300 [4]河南理工大学煤炭安全生产与清洁高效利用省部共建协同创新中心,河南焦作454000

出　　处：《煤炭转化》2023年第5期42-52,共11页Coal Conversion

基　　金：国家自然科学基金项目(52074109);河南省高校基本科研业务费专项资金项目(NSFRF220437).

摘　　要：煤沥青是一种原料来源丰富且含碳量高的钠离子电池碳负极材料。以煤沥青为碳源,通过炭化法制得热解炭,利用XRD,SEM,Raman光谱等表征技术,系统研究了不同炭化温度(600℃~1400℃)对煤沥青热解炭微观结构的影响规律。利用恒流充放电等测试,探究热解炭作为钠离子电池负极材料时的电化学性能,阐明“温度—结构—储钠性能”间的构效关系。结果表明:1000℃是热解炭微观结构从无序向有序发展的转折点;当温度低于1000℃时,热解炭为不规则的块状结构且表面平整光滑,未出现石墨微晶,具有较大的层间距和较高的无序度;当温度为800℃时,热解炭具有最大的层间距(d_(002)=0.3541 nm)和最高的无序度(I_(D)/I_(G)=2.57),其作为钠离子电池负极材料时,0.05 A/g电流密度下的可逆容量为177.0 mAh/g,首次库伦效率为73.87%,具有较好的倍率性能;当温度高于1000℃时,石墨碳层生长和堆叠的速度迅速加快,石墨化程度增加,层间距减小,同时表面缺陷程度降低,Na^(+)吸附位点减少,不利于储钠,热解炭具有较低的可逆容量(小于100 mAh/g)。Coal tar pitch is a carbon anode material for sodium-ion batteries with abundant raw material sources and high carbon content.Coal tar pitch was used as the carbon source to obtain pyrolytic carbon through carbonization.The influence of carbonization temperature(600℃-1400℃)on the microstructure and sodium storage behavior of coal tar pitch-derived pyrolytic carbon was systematically investigated using several characterization techniques such as XRD,SEM,Raman spectroscopy.The electrochemical properties of pyrolytic carbon as an anode material for sodium-ion batteries was investigated by means of constant current charge/discharge tests and the constitutive relationship between temperature,structure and sodium storage capacity was clarified.The results show that 1000℃serves as a turning point in the development of microstructure of pyrolytic carbon from disorder to order.When the temperature is less than 1000℃,the pyrolytic carbon exhibits irregular bulk structure with smooth surface,no apparent graphite microcrystals.In this case,the material has a larger interlayer spacing and a higher defect concentration.Pyrolytic carbon obtained at 800℃shows the maximum interlayer spacing(d_(002)=0.3541 nm)and the highest defect concentration(I_(D)/I_(G)=2.57).When used as anode material of sodium-ion batteries,it demonstrates a reversible capacity of 177 mAh/g at a current density of 0.05 A/g,with an initial coulombic efficiency of 73.87%and good rate performance.At temperatures above 1000℃,the growth and stacking rate of the graphitic carbon layers accelerate rapidly,resulting in higher graphitization degree,reduced interlayer spacing,decreased surface defect concentration,fewer Na^(+)adsorption sites,which is not conducive to sodium storage.Therefore,samples have a low reversible capacity(<100 mAh/g).

关 键 词：煤沥青 钠离子电池 负极材料 电化学性能 软碳 

分 类 号：TM911[电气工程—电力电子与电力传动]