纤维素衍生硬炭的结构调控和储钠性能研究

Structure Regulation and Sodium Storage Performance of Cellulose-Based Hard Carbon

刘海燕 苑仁鲁 龙厚坤 沈祺 赵博洋 刘学伟 宋怀河

Haiyan LIU Renlu YUAN Houkun LONG Qi SHEN Boyang ZHAO Xuewei LIU Huaihe SONG

山东能源集团有限公司 大型煤气化及煤基新材料国家工程研究中心，山东 济南 250101 北京化工大学 材料科学与;工程学院，北京 100029 兖矿鲁南化工有限公司，山东 滕州 277527

National Engineering Research Center of Coal Gasification and Coal-Based Advanced Materials，Shandong Energy Group;Co. ，Ltd. ，Jinan Shandong 250101，China School of Materials Science and Engineering，Beijing University of Chemical Technology，Beijing 100029，China Yankuang Lunan Chemicals Co. ，Ltd. ，Tengzhou Shandong 277527，China

纤维素来源丰富，易形成球形结构，是制备高性能储钠硬炭材料的重要前驱体。探究了天然纤维素、甲种纤维素、微晶纤维素等纤维素前驱体的结构及其在水热成球过程中的变化；分析纤维素衍生硬炭的微晶结构与其前驱体电化学储钠性能的关系，并优选了纤维素前驱体。结果表明，纤维素衍生硬炭的结晶度与纤维素前驱体的结晶度呈正相关；甲种纤维素衍生硬炭闭孔体积最大，缺陷密度适中，储钠容量最高，是最佳的纤维素前驱体；在220 ℃的温度下，对甲种纤维素进行水热处理，所得纤维素衍生硬炭呈球形形貌，并且兼具高储钠容量和倍率性能，在20、2 000 mA/g的电流密度下的可逆容量分别为329.4、53.9 mA·h/g。

Cellulose, due to its abundance and propensity to form spherical structures, serves as an exceptional precursor for the synthesis of high-performance hard carbon materials used in sodium-ion batteries. This study explores the interplay between different cellulose types, their structural evolution during hydrothermal spherization, and the subsequent impact on the microcrystalline characteristics and electrochemical performance of the resulting hard carbon for sodium storage. The results observed that the crystallinity of various cellulose precursors-namely natural cellulose, α-cellulose, and microcrystalline cellulose-and their corresponding hard carbons are positively correlated. Among these, hard carbon derived from α-cellulose demonstrated superior attributes, including the highest closed pore volume and a balanced defect density, which contribute to its enhanced sodium storage capacity. Furthermore, the hydrothermal treatment of α-cellulose at 220 °C was optimized to achieve a spherical morphology, which significantly benefited both the capacity and rate performance of the hard carbon. The reversible capacities at current densities of 20 and 2 000 mA/g are 329.4 and 53.9 mA·h/g, respectively.

国家自然科学基金项目(52172036);中国博士后科学基金资助项目(2024M750159);泰山产业领军人才工程资助项目(tscx202306116)

10.12422/j.issn.1006-396X.2024.06.007