Facile flame deposition of carbon coating onto Ni foam and the study of the derived carbon foam with high capacitive performance

Porous carbon foam was directly synthesized in an ethanol vapor flame within only 1 min for the first time. Nickel foam served as both hard template and catalyst substrate for catalyzing deposition of carbon coating on its surface. Carbon foam modified with oxygen-containing organic groups was obtained after etching the metal substrate. The following thermal treatment endowed the carbon foam with corrugated strut surface, decreased thickness of carbon strut layer, and reduced hetero-atom doping level. Moreover, the electrical conductivity of the foam was enhanced by >3 orders of magnitude up to 59.3 S m−1. Additionally, the free-standing thermal-annealed carbon foam electrode exhibited a desirable electric double-layer capacitance of 172 F g−1 at 2 Ag−1 in a three-electrode half-cell configuration, which could be due to its unique porous structure, high electrical conductivity, rich defects and oxygen-doping of the carbon foam.