0 引言
1 实验部分
1.1 实验材料及仪器
Table 1 Main experimental chemical reagents表1 主要实验化学试剂 |
试剂名称 | 化学式/简写 | 规格 | 生产厂商 |
---|---|---|---|
甲醛 | CH2O | 37% | 广州化学试剂 |
聚乙烯吡咯烷酮 | PVP | 29-32型 | 上海麦克林 |
聚四氟乙烯悬浮液 | PTFE | 60% | 美国杜邦 |
无水乙醇 | EtOH | 99.9% | 国药股份 |
硫 | S | 99.5% | 上海阿拉丁 |
氨丙基三乙氧基硅烷 | APTES | 99% | 上海阿拉丁 |
铝箔 | Al | — | 深圳新威 |
N-甲基吡咯烷酮 | NMP | 99.9% | 上海阿拉丁 |
聚偏二氟乙烯 | PVDF | 99.9% | 广州力柏能源 |
去离子水 | H2O | 电池级 | 自制 |
乙炔黑 | C | 电池级 | 力柏能源 |
盐酸 | HCl | 36% | 广州牌 |
1.2 氮氟共掺杂碳气凝胶的制备
1.3 氮掺杂碳气凝胶的制备
1.4 硫正极制备与锂硫电池组装
1.5 表征与测试
2 结果与讨论
2.1 NF-CA/S正极材料的制备
Fig. 1 Preparation flowchart of NF-CA/S cathode material图1 NF-CA/S正极材料的制备流程图 |
2.2 材料的表征
Fig. 2 SEM (a) and TEM (b) images of NF-CA; SEM (c) and TEM (d) images of NF-CA/S; (e) the morphology and elemental distribution of NF-CA/S图2 NF-CA的SEM(a)和TEM(b)图;NF-CA/S的SEM(c)和TEM(d)图;(e)NF-CA/S的形貌图与对应元素分布图 |
Fig. 3 (a) XRD curves of NF-CA, S, NF-CA/S; (b) Raman spectrum of NF-CA, S, NF-CA/S; (c) N 1s XPS spectra for NF-CA; (d) F 1s XPS spectra for NF-CA图3 (a)NF-CA、S、NF-CA/S的XRD图谱;(b)NF-CA、S、NF-CA/S的拉曼光谱;(c)NF-CA的N 1s XPS图谱;(d)NF-CA的F 1s XPS图谱 |
Fig. 4 (a) N2 adsorption-desorption isotherms of NF-CA and N-CA; (b) BJH porosity distribution of NF-CA; (c) BJH porosity distribution of N-CA; (d) TGA curves of NF-CA/S and S图4 (a)NF-CA与N-CA的氮气吸附-脱附等温线;(b)NF-CA的BJH孔径分布;(c)N-CA的BJH孔径分布;(d)NF-CA/S与S的TGA曲线 |
2.3 电化学性能测试
Fig. 5 (a) Cyclic voltammogram curves of NF-CA/S at 0.1 mV/s; (b-c) cycling performance at 1 C and rate performance of NF-CA/S and N-CA/S; (d) EIS curves of NF-CA/S and N-CA/S cathodes before and after cycling图5 (a)NF-CA/S材料在0.1 mV/s下的CV曲线;(b、c)NF-CA/S与N-CA/S材料的1 C循环曲线与倍率性能曲线;(d)NF-CA/S与N-CA/S制备的正极循环前后的EIS曲线 |
Fig. 6 (a) Visualization of Li2S6 adsorption experiment; (b) XPS elemental composition of Li2S6/NF-CA; (c) Li 1s XPS spectrum of Li2S6/NF-CA; (d) S 2p XPS spectrum of Li2S6/NF-CA图6 (a)可视化Li2S6吸附实验;(b)Li2S6/NF-CA的XPS元素组成;(c)Li2S6/NF-CA的Li 1s XPS图谱;(d)Li2S6/NF-CA的S 2p XPS图谱 |
Fig. 7 SEM images of Li-metal sheet (a, b) and NF-CA/S electrode (c, d) before and after 100 cycles图7 锂片(a、b)和NF-CA/S正极(c、d)循环100圈前后的SEM图 |