Liu Lianlian, Solin Niclas, Inganäs Olle
Department of Physics, Chemistry and Biology, Linköping University SE-581 83 Linköping Sweden
RSC Adv. 2019 Dec 2;9(68):39758-39767. doi: 10.1039/c9ra07507k.
Lignin is a promising candidate for energy storage because of its abundance, wide geographic distribution, and low cost as it is mainly available as a low value product from processing of wood into paper pulp. Lignin contains large amounts of potential quinone groups, which can be oxidized and reduced in a two electron process. This redox reaction makes lignin suitable for charge storage. However, lignin is insulating and therefore conductive materials are necessary in lignin electrodes, for whom the cost of the conductive materials hinders the scalable application. Among the organic conductive materials, graphite is one of the cheapest and is easily acquired from nature. In this work, we combine graphite and lignosulfonate (LS) and fabricate LS/graphite organic electrodes under a solvent-free mechanical milling method, without additives. The graphite is sheared into small particles with a size range from 50 nm to 2000 nm. Few-layer graphene is formed during the ball milling process. The LS/graphite hybrid material electrodes with primary stoichiometry of 4/1 (w/w) gives a conductivity of 280 S m and discharge capacity of 35 mA h g. It is a promising material for the scalable production of LS organic electrodes.
木质素因其储量丰富、地理分布广泛且成本低廉，有望成为一种储能材料，因为它主要是木材加工成纸浆过程中的低价值产物。木质素含有大量潜在的醌基团，这些基团可在双电子过程中被氧化和还原。这种氧化还原反应使木质素适合电荷存储。然而，木质素是绝缘的，因此在木质素电极中需要导电材料，而导电材料的成本阻碍了其规模化应用。在有机导电材料中，石墨是最便宜的之一，且易于从自然界获取。在这项工作中，我们将石墨和木质素磺酸盐（LS）结合，采用无溶剂机械研磨法制备了LS/石墨有机电极，且未添加任何添加剂。石墨被剪切成尺寸范围为50纳米至2000纳米的小颗粒。在球磨过程中形成了少层石墨烯。初级化学计量比为4/1（w/w）的LS/石墨混合材料电极的电导率为280 S/m，放电容量为35 mA h/g。它是一种有前景的材料，可用于规模化生产LS有机电极。
