Impact of pitch fraction oxidation on the structure and sodium storage properties of derived carbon materials  

沥青馏分氧化对衍生炭材料结构和储钠性能的影响

作　　者：QI Su-xia YANG Tao SONG Yan ZHAO Ning LIU Jun-qing TIAN Xiao-dong WU Jin-ru LI Hui LIU Zhan-jun 祁素霞;杨桃;宋燕;赵宁;刘均庆;田晓冬;武晋如;李慧;刘占军(中国科学院山西煤炭化学研究所炭材料山西省重点实验室,山西太原030001;中国科学院大学材料与光电研究中心,北京100049;中国科学院山西煤炭化学研究所煤转化国家重点实验室,山西太原030001;北京低碳清洁能源研究院,北京102211)

机构地区：[1]Shanxi Key Laboratory of Carbon Materials,Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,China [2]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China [3]State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,China [4]National Institute of Clean-and-Low-Carbon Energy,Beijing 102211,China

出　　处：《新型炭材料(中英文)》2025年第2期421-439,共19页New Carbon Materials

基　　金：国家自然科学基金(52072383,U21A2061,22209197)和山西省自然科学基金(202203021211002,2022023021222399).

摘　　要：Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation activity were studied.Several different carbon materi-als were produced from them by oxida-tion in air(350℃,300 mL/min)fol-lowed by carbonization(1000℃ in Ar),and the effect of the cross-linked structure on their structure and sodium storage properties was investigated.The results showed that the two pitch fractions were obviously different after the air oxidation.The TS fraction with a low degree of condensation and abundant side chains had a stronger oxidation activity and thus introduced more cross-linked oxygen-containing functional groups C(O)―O which prevented carbon layer rearrangement during the carbonization.As a result,a disordered hard carbon with more defects was formed,which improved the electrochemical performance.Therefore,the carbon materials derived from TS(O-TS-1000)had an obvious disordered structure and a larger layer spacing,giving them better sodium storage perform-ance than those derived from the TI-PS fraction(O-TI-PS-1000).The specific capacity of O-TS-1000 was about 250 mAh/g at 20 mA/g,which was 1.67 times higher than that of O-TI-PS-1000(150 mAh/g).本文将煤液化沥青分为可溶于甲苯(TS)和不溶于甲苯但溶于吡啶(TI-PS)的两个组分,研究了它们在分子结构和氧化活性方面的差异。此外,通过空气氧化(350℃,300 mL/min)和炭化(1000℃,Ar)合成了一系列沥青基炭材料并研究了产物的交联结构对衍生炭材料结构和钠储存性能的影响。结果表明,在空气氧化过程中,不同结构的沥青组分明显不同。缩合度低、侧链丰富的甲苯可溶组分(TS)表现出更强的氧化活性,从而引入了更多的交联含氧官能团C(O)―O。此外,交联结构可以防止炭化过程中炭层重排,形成缺陷更多的无序硬炭,有利于提高电化学性能。因此,由TS制备的衍生炭材料(O-TS-1000)具有明显的无序结构和较大的层间距,其储钠性能优于TI-PS制备的衍生炭材料(O-TI-PS-1000)。在20 mA/g时,比容量约为250 mAh/g,是O-TI-PS-1000(150 mAh/g)的1.67倍。

关 键 词：Pitch fractions Air oxidation Derived carbon materials Na+storage 

分 类 号：TQ127.11[化学工程—无机化工]