Facile synthesis of hierarchical mesopore-rich activated carbon with excellent capacitive performance
Facile synthesis of hierarchical mesopore-rich activated carbon with excellent capacitive performance
复制标题
轻松合成具有优异电容性能的多级孔富介孔活性炭
DOI：
10.1016/j.jcis.2019.03.059
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发表时间：
2019
影响因子：
9.9
通讯作者：
Li Kaixi
中科院分区：
文献类型：
--
作者：
Zhang Dongdong;He Chong;Zhao Jianghong;Wang Jianlong;Li Kaixi
介孔碳由于其在超级电容器中的潜在应用而引起越来越多的关注。迄今为止，窄孔径分布介孔碳的可控合成很大程度上依赖于复杂的模板方法。为了避免使用模板，提出了一种无表面活性剂乳液聚合方法，用于制造由微米级球形细胞和薄壁组装的三聚氰胺改性酚醛树脂微棒（MPRR）。此外，采用一步KOH活化策略，以MPRR为碳前驱体合成了具有2-10nm窄介孔的分级介孔活性炭。所制备的介孔活性炭具有约2758m2g−1的高比表面积和0.54cm3g−1的介孔体积（通过密度泛函理论计算），占总孔体积（～1.43cm3g−1）的~43.5%。分级介孔可以显着加速离子传输并增加微孔可达性，这赋予碳在6M KOH电解质中等于409Fg−1at 0.1Ag−1和268Fg−1at 100Ag−1的高比电容，并且电容保持率为66%。此外，组装的对称超级电容器在KOH电解液中也表现出良好的循环稳定性，当能量密度为5.02Whkg−1时，可提供高达12080Wkg−1的功率密度。这一发现为高性能超级电容器在分子水平上定向调控酚醛树脂基碳材料的介孔结构提供了见解。
Mesoporous carbons attract increasing attention owing to their potential applications in supercapacitors. So far, controlled synthesis of mesoporous carbons with a narrow pore size distribution relies largely on the complicated template methods. To avoid the use of templates, a surfactant–free emulsion polymerization method is presented for the fabrication of a melamine–modified phenolic resin microrod (MPRR) assembled by micron–sized spherical cells and thin walls. In addition, one–step KOH activation strategy is adopted to synthesize hierarchical mesoporous activated carbon with 2–10 nm narrow mesopores by using MPRR as carbon precursors. The as–prepared mesoporous activated carbon has a high specific surface area of about 2758 m2g−1and a mesopore volume of 0.54 cm3g−1(calculated by density functional theory), comprising ∼43.5% of total pore volume (∼1.43 cm3g−1). Hierarchical mesopores can significantly accelerate ion transfer and increase micropore accessibility, which endow the carbon with high specific capacitance equal to 409 F g−1at 0.1 A g−1and 268 F g−1at 100 A g−1in 6 M KOH electrolyte, with a high capacitance retention of 66%. Moreover, the assembled symmetric supercapacitor also exhibits good cycling stability in KOH electrolyte and delivers high power density equal to 12080 W kg−1when energy density is 5.02 Wh kg−1. This finding provides an insight into directional tailoring of mesoporous structures of phenolic resin–based carbon materials at the molecular level for high–performance supercapacitors.