Template-free fabrication of hierarchical porous carbon by constructing carbonyl crosslinking bridges between polystyrene chains

A simple and effective template-free method to fabricate hierarchical porous carbon (HPC) has been successfully developed by adopting linear polystyrene resin as raw material, anhydrous aluminium chloride as Friedel–Crafts catalyst, and carbon tetrachloride as crosslinker and solvent. Experimental results show that the as-constructed carbonyl (–CO–) crosslinking bridges between polystyrene chains provide simultaneously to its hierarchical porous polystyrene precursor, both a high crosslinking density and a proper amount of oxygen atoms, and thus achieve good framework carbonizability and nanostructure inheritability during carbonization. The as-prepared HPC's hierarchical porous structure exhibits interesting uniqueness: micropores (<2 nm) are from the network inside crosslinking polystyrene-based carbon nanoparticles of 10–30 nm in size, and mesopores (2–50 nm) and macropores (50–400 nm) result from the compact and loose aggregation of these network nanoparticles, respectively; and these micro-, meso- and macropores are three-dimensionally interconnected to each other. Its Brunauer–Emmett–Teller surface area and total pore volume are 679 m2g−1 and 0.66 cm3g−1, respectively.