Generalized Synthesis of a Family of Highly Heteroatom-Doped Ordered Mesoporous Carbons

High concentrations of heteroatom can be doped into ordered mesoporous carbon by infiltration of molten dopants into silica-reinforced mesoporous cross-linked polymer (resol) and subsequent carbonization. The high concentration of dopants relative to polymer enables a high probability of heteroatoms to be dynamically integrated into the framework through carbonization, while the silica in the framework prevents loss of the ordered structure. This method is demonstrated to generate ordered mesoporous carbons with high heteroatom content (up to 26 atom % N, 15 atom % B, 7 atom % P, or 4 atom % S) for a wide variety of elements through melt infusion of the appropriate dopant (melamine, boric anhydride, ammonium dihydrogen phosphate, or dibenzyl sulfide). The ratio of the solid dopants to mesoporous silica-resol in a physical mixture during the melt infusion provides a simple methodology to precisely tune the doping content in the carbonized material. Etching of the silica postcarbonization generates additional micropores to produce porous doped carbons with high surface areas that can exceed 2000 m²/g. Increasing the doping of the mesoporous carbon leads to a decrease in the surface area as the framework is swollen during the incorporation of the heteroatoms that leads to an increase in the d-spacing of the mesostructure, but the ordered structure is maintained with well-defined mesopores. With the advantages of high surface area, well-defined pore size, and tunable doping concentration through a straightforward methodology, it is expected that this family of mesoporous carbons will provide model materials for fundamental studies in diverse applications from energy storage to catalysis to adsorption for separations.