Ordered mesoporous carbons with body centred cubic pore structure

Abstract

The preparation of mesoporous carbons possessing a highly ordered body centred cubic (bcc) arrangement of pores by employing a halide- and metal-free synthesis method is reported. Products were characterised using gas physisorption, Small Angle X-ray Diffraction and X-ray Scattering, Raman spectroscopy and High Resolution Transmission Electron Microscopy (TEM). The materials produced in this work had Specific Surface Areas of between 422 and 988 m2g−1 and pore diameters of around 7 nm. From the TEM images, high quality Digital Diffraction Patterns, relating to the ordered mesopore structure, were obtained. On increasing calcination temperature from 350 to 1000°C the bcc structure was retained but its dimensions decreased progressively as the mesopore structure shrank. The effects on the structure and texture of the materials of the three key parameters of polymerisation time and the concentrations of the two catalysts employed, NH4OH and oxalic acid, were studied. Shorter polymerisation times and lower catalyst concentrations gave rise to the most well-ordered products whereas longer polymerisation times with higher concentrations of base and acid catalyst resulted in disordered pore structures.