Preparation and Properties of Nitrogen-Boron co-Doped Ordered Mesoporous Carbon

Utilizing novel m-carborane and 3-ethynylbenzenamine resin as precursor, ordered mesoporous carbon co-doped with nitrogen and boron NBC was successfully prepared by hard-template route. Methyl orange anionic dye was selected to investigate the adsorption behavior on NBC. The adsorption capacity of methyl orange dye on NBC and activated carbon (Ac) was studied using UV-Vis spectrophotometer. The effects of precursors molar ratio of B to N (n_B/n_N) on the texture and heteroatoms content of NBC were investigated. X-ray diffraction (XRD), N₂ adsorption and desorption and transmission electron microscopy (TEM) were used to characterize the morphology of prepared NBC samples. X-ray photoelectron spectroscopy (XPS) was used to investigate atomic percentage and bonding structure. Results showed that NBC had a two-dimensional hexagonal ordered structure with a pore size distribution centered at 3-6 nm. The increasing n_B/n_N (from 0.5 to 1.0) appropriately enhanced the pore size. However, when n_B/n_N increased from 1.0 to 2.0, NBC specific surface area and pore size gradually decreased and ordered structure was partially destroyed. When n_B/n_N was 1.0, NBC exhibited the highest specific surface area (1 560 m²/g) and the largest specific pore volume (1.92 cm³/g). Besides, the atomic percentage of boron and nitrogen could be adjusted to 4.95% and 6.32%, respectively. Compared to the conventional activated carbon adsorbent (61 mg/g), NBC-1.0 (n_B/n_N=1) exhibited rapid and effective adsorption performance (214 mg/g), which showed great potential as efficient adsorbent for removal of methyl orange dye.