Microwave-assisted synthesis of CoxP@C catalysts: Application to the hydrogenation of 1-chloro-4-nitrobezene

Transition metal phosphides (TMP) have gained great interest as catalysts for hydrogenation reactions due to their physical and chemical properties. Among these reactions, the hydrogenation of nitroarenes to the corresponding anilines is of great industrial importance, as these compounds are precursors of high value-added chemicals. In this work, we present the microwave-assisted synthesis of cobalt phosphide nanoparticles supported on carbon, and its application in the hydrogenation of 1-chloro-4-nitrobenzene. The catalysts were characterised by transmission electron microscopy (TEM), temperature-programmed reduction (TPR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and N2 adsorption at -196 degrees C. It could be observed that the catalytic activity depends on the reduction temperature, since it determines the crystalline phase of the phosphide. Thus, we found that the most active phase for the hydrogenation of 1-chloro4-nitrobenzene corresponds to a phosphorus-rich cobalt phosphide obtained at low reduction temperatures.