Processing, growth mechanism and thermodynamic calculations of carbon foam with a hollow tetrapodal morphology – Aerographite

•Growth mechanism of a 3D carbon foam, called Aerographite is shown via ex situ analysis.•The growth mechanism is based on the graphitization of amorphous carbon into graphitic carbon.•The produced by-products are causing to defects in the formed carbon wall.•A negative Gibbs free energy is calculated, which is resulting in a voluntary reaction.•Based on the growth mechanism, the wall thickness can be tailored.