Nitrogen doped bimodal cellular structure activated carbon produced

New monolithic nitrogen-containing microporous cellular activated carbon was successfully prepared from phenol-urea-formaldehyde (PUF) organic foam for CO₂ and H₂ adsorption. The macroporosity corresponded to the connected network of cells with diameters ranging from 100 to 600 µm, and the pinholes in the cell walls had diameters ranging from 1 to 2 µm. The micro/mesoporosity is located at the inner surface of the cells.

Cellular activated carbon, a new type of activated carbon we prepared, is based on carbon foams, the inner surfaces of which are activated physically by CO₂ to generate an available surface made up of micro/mesopores. The carbon foams are enriched with macropores that are connected to the cell walls. After activation, the cellular activated carbon produces a great deal of micro and mesopores at the surface of the macropores; therefore, this new bimodal cellular activated carbon can be used just like the classic activated carbon as an adsorbent, catalyst support, energy storage and biological material in various industries.

But the most difference is the ACs are normally in the form of grains or are granular with surface areas mainly being controlled by their inner microporosity (pore size less than 2 nm) and mesoporosity (pore size ranging from 2 to 50 nm). The mesoporosity also plays a role in the pathways for reactants flowing through the carbon grains. When we using this carbon foam as a precursor provides pathways for the macropores, so the resulting features for the new cellular activated carbon are the monolithic shape and high adsorption kinetics due to the size of the bigger pores.