Synthesis of mesoporous carbon/iron carbide hybrids with unusually high surface areas from the ionic liquid precursor [Bmim][FeCl4]

Abstract

Mesoporous carbon/iron carbide hybrid materials with surface areas reaching 800 m² g⁻¹ were synthesized via an exotemplating route using monolithic mesoporous silica as template and the ionic liquid 1-butyl-3-methylimidazolium tetrachloridoferrate(III) [Bmim][FeCl₄] as carbon and iron source. After heat treatment (750 °C under argon) of the [Bmim][FeCl₄] precursor confined within the silica matrix, the silica exotemplate was removed with HF leaving the mesoporous C/Fe₃C hybrid behind. The surface areas and the pore sizes depend on the exotemplate and the surface areas a significantly larger than any other surface area reported for C/Fe₃C hybrid materials so far. The approach is thus a prototype for the synthesis of high-surface area iron carbide-based hybrid materials with potential application in catalysis.