Mesopore-dominated porous carbon derived from vinasse for high performance supercapacitors with different electrolytes

Porous carbon electrode materials with appropriate proportion of hierarchical pores are critical for high performance supercapacitors. Here, a mesopore-dominated hierarchical porous carbon was reported. KOH, melamine (MA), and the carbonized vinasse were sequentially mixed using dry ball milling, the mixture was pyrolyzed to acquire mesopore-dominated porous carbon. The pore structure can be controlled by adjusting the addition amount of melamine. The optimal sample with high meso-porosity, large total pore volume, ultrahigh specific surface area (SSA) and hydrophilicity makes it performs quite well in different electrolytes. A high specific capacity of 413 F g−1 was achieved and retained 267 F g−1 at a high rate of 50 A g−1 with excellent capacitance retention (107 % after 10000 cycles). The symmetrical supercapacitor gained a superior energy density of 16.7 Wh kg−1, 21.2 Wh kg−1, 54.0 Wh kg−1 in 6 M KOH, 1 M Na2SO4, 1 M Et4NBF4/ACN electrolyte, respectively. This work opens a new strategy for the preparation and high-efficient application of biomass porous carbon materials in energy storage.