Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology , Hefei 230009, P. R. China.
Materials Science and Engineering Program & Texas Materials Institute, The University of Texas at Austin , 1 University Station, C2201, Austin, Texas 78712, United States.
ACS Appl Mater Interfaces. 2017 Oct 4;9(39):33855-33862. doi: 10.1021/acsami.7b09310. Epub 2017 Sep 25.
Retaining soluble polysulfides in the sulfur cathodes and allowing for deep redox are essential to develop high-performance lithium-sulfur batteries. The versatile textures and physicochemical characteristics of abundant biomass offer a great opportunity to prepare biochar materials that can enhance the performance of Li-S batteries in sustainable mode. Here, we exploit micro-/mesoporous coconut shell carbon (CSC) with high specific surface areas as a sulfur host for Li-S batteries. The sulfur-infiltrated CSC materials show superior discharge-charge capacity, cycling stability, and high rate capability. High discharge capacities of 1599 and 1500 mA h g were achieved at current rates of 0.5 and 2.0 C, respectively. A high reversible capacity of 517 mA h g was retained at 2.0 C even after 400 cycles. The results demonstrate a high retention and a deep lithiation of the CSC-confined sulfur. The success of this strategy provides insights into seeking high-performance biochar materials for Li-S batteries from abundant bioresources.
在硫正极中保留可溶性多硫化物并允许进行深度氧化还原反应对于开发高性能锂硫电池至关重要。丰富生物质的多功能纹理和物理化学特性为制备生物炭材料提供了绝佳机会，这些材料可以以可持续的方式提高 Li-S 电池的性能。在这里，我们利用具有高比表面积的微孔/介孔椰子壳碳 (CSC) 作为 Li-S 电池的硫主体。浸渍硫的 CSC 材料表现出优异的放电-充电容量、循环稳定性和高倍率性能。在 0.5 和 2.0 C 的电流速率下，分别实现了 1599 和 1500 mA h g 的高放电容量。即使在 400 次循环后，在 2.0 C 时仍保持了 517 mA h g 的高可逆容量。结果表明，CSC 限制的硫具有高保留率和深度锂化。该策略的成功为从丰富的生物资源中寻找用于 Li-S 电池的高性能生物炭材料提供了新的思路。
