Synthesis of Highly Microporous Sulfur-Containing Activated Carbons by a Multistep Modification Process

The sulfur-containing activated carbons(SACs)were prepared by CO2 activation and sulfur impregnation.The sulfur-containing samples were then oxidized in air.The SACs were characterized by N2 adsorption,elemental analysis,thermogravimetric analysis,X-ray photoelectron spectroscopy,Raman spectroscopy,and X-ray diffraction.The CO2 activation provided precursor carbons with high porosity,which in turn were sulfurized effectively.Oxidation in air at 200℃enlarged pores and redistributed amorphous sulfur in the hierarchical pores.A typical SAC containing 17.89%sulfur exhibited a surface area of 1464 m2/g.This work may open up a valid route to prepare highly microporous SACs with high sulfur loading for applications where the presence of sulfur is beneficial.