Hard carbon anode materials have attracted wide attention for the development of practical sodium ion batteries. However, the effect of the structure of pyrolytic precursor on sodium storage performance of the hard carbon was rarely reported. In this article three different carbohydrate precursors are chosen to investigate the influence of their molecular weight on the microstructure and sodium storage property of the final pyrolyzed hard carbons. Results of X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy (Raman) showed that the graphitization degree of the hard carbon materials increases with molecular weight of their precursors. The reversible specific capacity of the hard carbons with glucose, sucrose and starch as precursors reached 242, 275 and 310 mA·h/g respectively, indicating its proportional relationship with the molecular weight of the precursors, and a precursor with high molecular weight is easier to form a more regular graphite-sheet structure, thereby providing more fitted and more sodium reaction sites. This work provides a reference for selecting the precursor of hard carbon as anode material of sodium-ion batteries.
邱 珅，吴先勇，卢海燕，艾新平，杨汉西，曹余良. 不同分子量前驱物热解硬碳负极材料的储钠性能[J]. 储能科学与技术, 2016, 5(3): 335-340.
QIU Shen, WU Xianyong, LU Haiyan, AI Xinping, YANG Hanxi, CAO Yuliang . Sodium storage performance of hard carbons prepared by pyrolyzing precursors with different molecular weight. Energy Storage Science and Technology, 2016, 5(3): 335-340.