Synthesis of Phase-Pure W _<b>2</b> C and WC by Separation of Reduction and Carburization and Their Differing Performance as Hydrogenation Catalysts

High Resolution Image Download MS PowerPoint Slide Tungsten carbide is considered a promising, low-cost alternative to noble metal catalysts due to its electronic properties being similar to those of platinum. However, the role of the different tungsten carbide modifications (W 2 C, WC) in catalysis is rather unclear so far. Conventionally, tungsten carbide synthesis for catalytic applications is performed via a highly complex gas–solid reaction with the simultaneous reduction and carburization of tungsten(VI)oxide. This work explores a less-investigated two-step synthesis, decoupling reduction, and carburization to obtain and investigate both phase-pure tungsten semicarbide and tungsten monocarbide. Time-resolved analyses of the solid-state reactions concerning reduction and carburization were performed by in situ XRD. This alternative approach allowed the synthesis of phase-pure W 2 C and WC bulk materials with comparable morphological properties. The performance of the resulting catalysts was tested in the hydrogenation of butyraldehyde to 1-butanol. The higher hydrogenation activity of W 2 C over WC is in accordance with previous theoretical investigations.