Abstract:

Unlike terrestrial plants, algae usually contain a large amount of alginate, which mainly exist in the cell wall in the forms of calcium alginate and magnesium alginate. In order to maintain the “egg-box” structure of calcium alginate in kelp, the carbonized products of kelp were treated by hydrochloric acid pickling to remove calcium ions from calcium alginate and to form the initial “egg-box” pore structure. Then kelp-based activated carbon was prepared by KOH activation method. The pore structure and electrochemical properties of kelp-based activated carbon were investigated. The experimental results showed that the kelp-based activated carbon with “egg-box” structure had abundant pore structure, and its specific surface area was as high as 3027m²/g, 73.3% of which was from the mesopores with uniform pore size in the range of 2—10nm. The kelp-based activated carbon exhibited excellent electrochemical performance in alkaline electrolyte. When the current density was 0.1A/g, the specific capacitance of the kelp-based activated carbon reached 366F/g. Even when the current density was 10A/g, the specific capacitance still maintained 329F/g, showing good specific capacitance and rate performance.

Key words: biomass, activated carbon, “egg-box” structure, preparation, electrochemistry

摘要：

与陆生植物不同，海藻中通常含有大量的海藻酸和海藻酸盐，其中海藻酸盐主要以海藻酸钙、海藻酸镁等形式存在于细胞壁中。本文利用海带中海藻酸钙的“蛋盒”式结构，对海带炭化产物进行盐酸酸洗处理，除去海藻酸钙中的钙离子，形成“蛋盒”式初始孔结构，然后采用KOH活化法制备海带基活性炭，研究海带基活性炭的孔结构特性以及电化学性能。实验结果表明：基于“蛋盒”结构制备的海带基活性炭拥有丰富的孔隙结构，其比表面积高达3027m²/g，其中73.3%由中孔比表面积提供，且中孔孔径分布比较集中，几乎全部分布在2～10nm。海带基活性炭在碱性电解液中展现出优秀的电化学性能，当电流密度为0.1A/g时，其比电容高达366F/g，即使在电流密度为10A/g的条件下，活性炭比电容仍然高达329F/g，显示出良好的比电容性能和倍率性能。

关键词: 生物质, 活性炭, “蛋盒”结构, 制备, 电化学