Thick wall mesoporous carbons with a large pore structure templated from a weakly hydrophobic PEO–PMMA diblock copolymer

Abstract

Thick wall mesoporous carbons (FDU-18) with ordered large pore structures were synthesized via an evaporation induced self-assembly (EISA) approach by using a novel amphiphilic diblock copolymer with a weakly hydrophobic segment as a template, soluble resol as a carbon source and THF as a solvent. The versatile atom transfer radical polymerization (ATRP) method was utilized to prepare the diblock copolymer, poly(ethylene oxide)-b-poly(methyl methacrylate) (PEO-b-PMMA). ¹H NMR spectroscopy and gel permeation chromatography show that the obtained PEO-b-PMMA has a M_n of 20 070 g mol⁻¹ and a narrow molecular weight distribution (1.09). Small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) measurements demonstrate that the obtained mesoporous carbons have a face centered cubic close-packed mesostructure (Fmm) with a large unit cell (∼38 nm). N₂ sorption isotherms indicate that the mesoporous carbons have a high surface area up to 1050 m² g⁻¹ and a uniform large mesopore (∼10.5 nm). It is interesting that the pore walls of the mesoporous carbonaceous materials are ultra thick (ca. 11.5–12.4 nm), which are even larger that their pore diameters. The thick pore walls are related to the weakly hydrophobic block PMMA, which can associate with the phenolic resol precursors. Many useful performances such as high mechanical/chemical stability and graphitization could be expected for this kind of thick wall carbon material.