Synthesis of mesoporous tungsten carbide by an impregnation–compaction route, and its NH3 decomposition catalytic activity

Abstract

A mesoporous tungsten carbide (WC) with high surface area (138 m2 g(-1)) has been synthesized at 700 degrees C using a modified template replicating route in which the pore entrances were sealed under external pressure after the W source impregnation. X-Ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX) spectroscopy and nitrogen sorption techniques were employed to characterize the replicated material. The prepared tungsten carbide with high surface area is well crystallized and has a partially ordered mesoporous structure. Temperature programmed reaction (TPR) and time-on-stream (TOS) results show that the prepared mesoporous tungsten carbide has high and stable catalytic activity for the decomposition reaction of NH3, and the complete NH3 decomposition temperature was obtained at 500 degrees C. This mesoporous WC appears to be a good catalyst for use for NH3 decomposition.