Abstract
Closed pores formed in hard carbons play an essential role in sodium storage at plateau region.How-ever,the effect of different structural features on the diffusion of sodium ions into closed pores remains unclear.Herein,a precursor reconstruction strategy is conducted to regulate carbon microstructures in-cluding interlayer spacing,defect concentration,and closed pore volume by changing the ratio of aro-matic and polysaccharide components.Aromatic structure parts tend to develop disordered carbons with fewer defects,larger interlayer spacing,and smaller closed pore volume,while polysaccharide compo-nents prefer to form disordered carbons with more defects,smaller interlayer spacing,and larger closed pore volume.Through the correlation analysis of microstructure features and the sodium storage capac-ity below 0.1 V.It finds that the intercalation capacity is proportional to the ratio of pseudo-graphitic domains,whereas the pore filling capacity appeared at lower potential gradually decreases with the in-creasing defect concentration due to homo-ionic repulsion effect,without linear correlation with short-range microcrystalline and closed pore volume.The optimized sample with suitable interlayer spacing and defect concentration exhibits a high plateau capacity of 241.7 mAh/g.This work provides insights into the exploitation of closed pore sodium storage performance.
基金项目
National Key Research and Development(R&D)Program of China(2020YFB1505803)
Youth Innovation Promotion Association of CAS(2019178)
Innovation Fund for Basic Research Program supported by ICC CAS(SCJC-XCL-2023-10)
Innovation Fund for Basic Research Program supported by ICC CAS(SCJC-XCL-2023-13)
NETL
NSTL
万方数据