不同生物炭材料的制备及其在Li-S电池中的应用（英文）

发布时间：2018-09-19 06:20

【摘要】：通过可再生生物质制备的生物炭具有成本低、环保和资源可再生的优势。本研究以分布广泛的稻谷壳、芒草、杉木和柚子皮等生物质为原料,制备了4种不同类型生物炭,然后研究了其作为锂-硫电池硫/碳正极的载体的性能。研究表明由稻谷壳制备的硫/生物炭正极材料表现出最高的比容量和最优的循环稳定性。为了进一步改善其电性能,以SiO_2溶胶为模板制备了具有高孔隙率的稻谷壳生物炭,其多孔结构可有效抑制多硫化物的溶解。由此得到的硫/生物炭(硫含量为60%(w,质量分数))材料中的硫以无定型态均匀地分散在碳载体中。该材料表现出更优异的电化学性能:在0.2C(1C=1675 m A?g~(-1))倍率下,首周放电容量为1534.1 mAh?g~(-1),循环100周后仍可保持在783.7 mAh?g~(-1);倍率性能测试中,在2.0C倍率下,材料的可逆容量为485.3 mAh?g~(-1)。
[Abstract]:Biochar prepared from renewable biomass has the advantages of low cost, environmental protection and renewable resources. In this study, four different types of biochar were prepared from widely distributed biomass such as rice husk, mango, Chinese fir and pomelo peel, and their properties as carriers of sulfur / carbon positive electrode of lithium-sulfur battery were studied. The results showed that the sulfur / biochar cathode materials prepared from rice husks showed the highest specific capacity and optimal cycling stability. In order to further improve its electrical properties, rice husk biochar with high porosity was prepared by using SiO_2 sol as template, and its porous structure could effectively inhibit the dissolution of polysulfide. The sulfur in the resulting sulfur / biochar (sulfur content is 60% (w, mass fraction) is uniformly dispersed in the carbon carrier in an amorphous form. The material showed better electrochemical performance: the discharge capacity at the first cycle was 1534.1 mAh?g~ (-1) at 0.2C (1C=1675 m Agng ~ (-1) and remained at 783.7 mAh?g~ (-1) after 100 cycles, and the reversible capacity of the material was 485.3 mAh?g~ (-1) at 2.0 C ratio.
【作者单位】：厦门大学能源学院;厦门大学化学化工学院;
【基金】：supported by the National Natural Science Foundation of China(21373008) Fundamental Research Funds for the Central Universities,China(20720160124)~~
【分类号】：O613.71;TM912

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