Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6471247 | Electrochimica Acta | 2017 | 10 Pages |
â¢We first utilize oily sludge to fabricate three-dimensional hierarchical porous carbon (HPC) material.â¢The as-fabricated HPC exhibits super-high surface area and rational pore size distribution.â¢Outstanding performance of the HPC is demonstrated in all-solid-state flexible supercapacitor.â¢The cost of oily sludge-based HPC material is negligible.
Rationally packed porous carbon with high ion-accessible surface area and low ion-transport resistance is proved to be an excellent candidate as electrode materials in high performance supercapacitors. However, its cost-effective fabrication still remains a significant challenge. Here, we report on a novel three-dimensional hierarchical porous carbon (HPC) synthesized via a facile and low-cost approach from hazardous waste oily sludge for the first time. Both the smart “self-template” effect and appropriate activation effect are crucial for the rational hierarchical porous structure. The “self-template” procedure is the key point for creating the skeleton of carbon, and the KOH activation process is able to regulate pore size distribution and increase specific surface area. The as-fabricated HPC possesses favorable features for supercapacitor, such as outstanding specific surface area (2561Â m2Â gâ1), large pore volume (2.25Â cm3Â gâ1), tunable and large range of pore size distribution. The HPC-based electrode can deliver an admirable capacitance of 348.1Â FÂ gâ1 at 0.5Â AÂ gâ1 and 94.3% capacitance retention at 5Â AÂ gâ1 after 10,000 cycles in aqueous electrolyte. Remarkably, the all-solid-state HPC//HPC symmetric supercapacitor displays outstanding capacitance of 81.3Â FÂ gâ1 at 0.5Â AÂ gâ1 with high energy density of 7.22Â W h kgâ1. It is demonstrated that the strategy developed here would provide cost-effective production of HPC electrode material for high performance supercapacitors and offer a promising avenue of large-scale fabrication of HPC from other hazardous industrial waste.
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