文献类型：期刊文献

英文题名：Fabricating a high-energy-density supercapacitor with asymmetric aqueous redox additive electrolytes and free-standing activated-carbon-felt electrodes

作者：Tian, Meng[1];Wu, Jiawen[1];Li, Ruihan[1];Chen, Youlin[1];Long, Donghui[1,2]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Shanghai Key Lab Multiphase Mat Chem Engn, Shanghai 200237, Peoples R China

年份：2019

卷号：363

起止页码：183

外文期刊名：CHEMICAL ENGINEERING JOURNAL

收录：;EI(收录号：20190506439893);WOS:【SCI-EXPANDED(收录号:WOS:000457866400018)】；

基金：This work was partly supported by MOST (2014CB239702) and National Science Foundation of China (No. 21576090), and Fundamental Research Funds for the Central Universities (222201718002).

语种：英文

外文关键词：Asymmetric supercapacitor; High energy density; Redox additive; Asymmetric electrolyte; Free-standing electrodes

摘要：Aqueous carbon-based supercapacitors are now reaching the energy density limits set by electric double layer mechanism and water decomposition voltage window. Here, we construct a high-energy-density carbon-based supercapacitor with a new strategy of asymmetric electrolyte design by adding K-3[Fe(CN)(6)] and 2,6-dihydroxyanthraquinone (2,6-DHAQ) as positive and negative redox additives in 2 M KOH solution respectively. Modified activated carbon felt (ACF) serves as low-cost free-standing electrodes with no binders and conducive additives, porous structure of which facilitates excellent electrolyte permeability and fast ion transport. And it shows great potential for large-scale energy storage due to unique flexible and scalable properties. The corresponding supercapacitor integrating the advantages of redox activity of K-3[Fe(CN)(6)] in positive potential and 2,6-DHAQ in negative potential achieves higher ion utilization, extended operation window to 2 V, high cell capacitance of 79 F g(-1) and excellent cycling performance with 84% capacitance retention after 5000 cycles. Most importantly, it delivers high energy density of 39.1 Wh kg(-1) maintaining superior power density, much higher than those of previously reported supercapacitors with symmetric aqueous redox electrolytes. The asymmetric redox additives in aqueous electrolytes for ACF-based supercapacitors may represent a new approach to high-performance energy storage.