采用两步炭化法和熔盐模板法制备N、S共掺杂煤基硬炭及共储钠性能OA北大核心CSTPCD

Hard carbon,known for its abundant resources,stable structure and high safety,has emerged as the most popular an-ode material for sodium-ion batteries(SIBs).Among various sources,coal-derived hard carbon has attracted extensive attention.In this work,N and S co-doped coal-based carbon material(NSPC1200)was synthesized through a combination of two-step carboniza-tion process and heteroatom doping using long-flame coal as a carbon source,thiourea as a nitrogen and sulfur source,and NaCl as a template.The two-step carbonization process played a crucial role in adjusting the structure of carbon microcrystals and expanding the interlayer spacing.The N and S co-doping regulated the electronic structure of carbon materials,endowing more active sites.Ad-ditionally,the introduction of NaCl as a template contributed to the construction of pore structure,which facilitates better contact between electrodes and electrolytes,enabling more efficient transport of Na+and electrons.Under the synergistic effect,NSPC1200 exhibited exceptional sodium storage capacity,reaching 314.2 mAh g-1 at 20 mA g-1.Furthermore,NSPC1200 demonstrated com-mendable cycling stability,maintaining a capacity of 224.4 mAh g-1 even after 200 cycles.This work successfully achieves the stra-tegic tuning of the microstructure of coal-based carbon materials,ultimately obtaining hard carbon anode with excellent electrochem-ical performance.