Sustainable straightforward synthesis of hierarchically porous graphitised carbon foams with nanodispersed magnetite and elemental iron particles

This study presents a straightforward synthesis method for producing 3D carbon foams with specific characteristics, including an open macroporous structure combined with microporosity and mesoporosity, as well as the nanodispersion of various iron species within the carbonaceous matrix. The process involves thermo-foaming and carbonisation of sucrose in the presence of an iron nitrate additive, resulting in ordered carbon structures with reduced oxygen content and finely nanodispersed iron species particles within the carbon matrix. The properties of the resulting material vary based on the proportion of the additive and the carbonisation temperature, highlighting the versatility of the method in producing different materials for diverse plications. Above 800 °C, iron nitrate reacts to form Fe 3 O 4 and Fe 0 , which catalytically influence the foam structure. Graphitisation consistently occurs between 800 and 900 °C, facilitated by the fine nanodispersion of iron species. The combination of an open macroporous nature with microporosity and mesoporosity, along with a partially graphitised carbonaceous matrix containing nanodispersed active iron species, makes these materials promising candidates for valuable applications such as adsorption, catalysis, and biomedical uses. • Environmentally acceptable synthesis method of carbon foams. • Iron species significantly influence the structure of the carbon foam. • Graphitisation occurs between 800 and 900 °C, favoured by iron species particles. • The presence of iron species enables the generation of micro- and mesoporosity.