Ji Shiyu, Yang Jie, Cao Jianyun, Zhao Xin, Mohammed Mahdi A, He Pei, Dryfe Robert A W, Kinloch Ian A
Department of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom.
Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.
ACS Appl Mater Interfaces. 2020 Mar 18;12(11):13386-13399. doi: 10.1021/acsami.0c01216. Epub 2020 Mar 5.
Electrodeposition of conducting polymer-carbon composites from an electrolyte precursor solution is a facile one-step approach to fabricate device-ready electrodes for energy storage. A key challenge in this approach is the dispersion of the carbon nanomaterials with the aqueous precursor solution with previous approaches either heavily oxidizing the carbon nanomaterials or using high concentrations of anionic surfactants as dopants. However, the former reduces the electrical conductivity of carbon, while the latter reduces the ionic mobility of the conducting polymer due to the large anion size. Herein, for the first time we present a quaternary electrolyte formulation for the fabrication of pristine carbon and polypyrrole (PPy) composites that does not sacrifice either electron or ion mobility. The electrolyte uses lithium perchlorate (20 mM) as a supporting electrolyte and dopant, sodium dodecylbenzenesulfonate at a very low concentration (1.43 mM) as a surfactant, together with pristine carbon nanomaterials and pyrrole monomers. The order of magnitude difference between the concentration of the dopant and surfactant ion allows the as-deposited PPy to be doped predominantly by small-sized and mobile perchlorate anions. Composites of PPy with carbon black, carbon nanotubes, and electrochemical exfoliated graphene (EEG) have been successfully prepared using this new quaternary electrolyte. The as-fabricated PPy/EEG composite electrodes showed a specific capacitance of 348.8 F g with a high rate capability (190.7 F g at 71 A g). Supercapacitor devices based on the PPy/EEG composite electrodes exhibit a high rate behavior up to 500 mV s and a long cycle life of 5000 cycles.
从电解质前驱体溶液中电沉积导电聚合物-碳复合材料是一种简便的一步法，用于制备可直接用于储能器件的电极。这种方法的一个关键挑战是将碳纳米材料与水性前驱体溶液分散，以往的方法要么严重氧化碳纳米材料，要么使用高浓度的阴离子表面活性剂作为掺杂剂。然而，前者会降低碳的电导率，而后者由于阴离子尺寸较大，会降低导电聚合物的离子迁移率。在此，我们首次提出一种用于制备原始碳和聚吡咯（PPy）复合材料的四元电解质配方，该配方不会牺牲电子或离子迁移率。该电解质使用高氯酸锂（20 mM）作为支持电解质和掺杂剂，极低浓度（1.43 mM）的十二烷基苯磺酸钠作为表面活性剂，同时加入原始碳纳米材料和吡咯单体。掺杂剂和表面活性剂离子浓度之间的数量级差异使得沉积的PPy主要由小尺寸且可移动的高氯酸根阴离子掺杂。使用这种新型四元电解质已成功制备了PPy与炭黑、碳纳米管和电化学剥离石墨烯（EEG）的复合材料。制备的PPy/EEG复合电极显示出348.8 F g的比电容和高倍率性能（在71 A g时为190.7 F g）。基于PPy/EEG复合电极的超级电容器器件表现出高达500 mV s的高倍率性能和5000次循环的长循环寿命。
