Self-deposition for mesoporous carbon nanosheet with supercapacitor application

Porous carbon sheets have wide application prospects in many fields, especially in energy storage of supercapacitor due to the features combining both 2D structure and porous architectures. Herein, a self-deposition approach is proposed to obtain N-doped mesoporous carbon nanosheets (N-MCNs), using 3-aminophenol (3-AF) as precursor and Mg(OH)2 sheet as hard template. This process realizes the direct carbon formation using 3-AF monomer as carbon precursor under the catalysis of hard template avoiding the polymerization and utilization of solvent. The mass ratio of 3-AF to Mg(OH)2 plays an important role in determining the pore structures and the resulting capacitance behavior. The results show that N-MCNs with a mass ratio of 3-AF and Mg(OH)2 of 1:1 have good electrochemical behavior for supercapacitors. This N-MCNs based electrode exhibits a high capacitance of 240 F·g−1 at 1 A·g−1, good rate performance (75.4% retention ratio at 20 A·g−1), and high cycling stability with 98.3% initial capacitance retained after 10000 cycles. Symmetric supercapacitors on N-MCNs achieve energy density of 18.2 W·h·kg−1 and power density of 0.4 kW·kg−1 operated within a wide potential range of 0–1.6 V in 1.0 mol·L−1 Na2SO4 solution, exhibiting its potential for electrode materials with high performance.