Fabrication of Hierarchical Macroporous/Mesoporous Carbons via the Dual-Template Method, and the Restriction Effect of Hard Template on Shrinkage of Mesoporous Polymers

A series of hierarchically ordered macro-/mesoporous polymer resins and macro-/mesoporous carbon monoliths were synthesized using SiO2 opal as a hard template for the macropore, amphiphilic triblock copolymer PEO-PPO-PEO as a soft template for the mesopore, and phenolic resin as a precursor for the polymer or carbon. The obtained hierarchical macro-/mesoporous frameworks had highly periodic arrays of uniform macropores that were surrounded by walls containing the mesoporous structures. The mesoporous, structure of the walls was adjusted using different precursors for the synthesis of FDU-14, FDU-15, and FDU-16. Results of the N-2 adsorption-desorption analysis showed that the Bninauer-Emmett-Teller surface areas, the pore volumes, and the mesopore sizes of the macro-/mesoporous carbons were much larger than those of the FDU-14, FDU-15, and FDU-16 carbon materials. The mesopore size of the samples clearly increased with the increasing heat-treatment temperature when the temperature was below 700 degrees C. The results indicate That the SiO2 hard template successfully restricted the shrinkage of the framework during the thermosetting and carbonization process(.)