微孔共轭聚合物热解制备氮、硫杂原子硬炭及其储锂性能

选取溴代噻唑和三乙炔基苯为单体，利用聚合反应自下而上构建含噻唑共轭微孔聚合物(NSCMP)，通过热解和KOH活化热解NSCMP制备了氮、硫杂原子硬炭(NSHC)和活化NSHC(KNSHC)。利用扫描电子显微镜、能量色散谱、氮气吸附-脱附和恒流充放电等表征2个样品的结构与电化学性能。研究表明KNSHC中N和S的质量分数分别为10.42%和2.23%，KNSHC比表面积高达2 140 m²·g^-1。在0.2 A·g^-1电流密度下循环500次后KNSHC和NSHC的可逆比容量分别为946.2和493.7 mAh·g^-1。KNSHC的优异电化学性能归因于其独特的孔结构和氮、硫杂原子的协同作用。

Preparation and lithium storage properties of nitrogen, sulfur heteroatom hard carbon by pyrolysis of conjugated microporous polymers

A bottom-up approach was employed to build a thiazole-containing conjugated microporous polymer (NSCMP) by choosing bromo-thiazole and triacetylene benzene as monomers. The pyrolyzation and KOH-assisted pyrolyzation of NSCMP were performed to obtain the N, S heteroatom hard carbon (NSHC) and KOH-activated NSHC (KNSHC). NSHC and KNSHC were further characterized by scanning electronic microscope, energy-dispersive spectra (EDS), nitrogen adsorption-desorption, galvanostatic charge-discharging test, etc. The EDS revealed that the N and S mass fractions of KNSHC were 10.42% and 2.23%, respectively. The specific surface area of KNSHC was as high as 2 140 m²·g^-1, which was distinctly higher than that of NSHC (657 m²·g^-1). The specific capacity of KNSHC after 500 cycles at 0.2 A·g^-1 was as high as 946.2 mAh·g^-1, while that of NSHC was only 493.7 mAh·g^-1. The excellent electrochemical performance of KNSHC may be due to the synergistic effect of N and S heteroatoms as well as the unique porous structure.