Reactivity of Black Phosphorus with Pd Compounds

Since its first reported exfoliation in 2014, the interest in 2D black phosphorus (2D BP) and its chemical functionalization has grown dramatically [1], though a satisfactory structural description of the modified materials is seldom achieved. Herein, the functionalization of 2D BP starting from molecular Pd precursors is presented, leading either to supported Pd NPs (Pd/BP) or to interlayer Pd-Pd discrete units (Pd2/BP). An in-depth solid-state characterization of the new materials was carried out by means of XPS, HAADF-STEM, XRD, NMR MAS and XAS. Remarkably, XAS analysis, backed up by DFT modelling, was crucial in revealing the existence of Pd2 moieties stacked amidst BP layers in Pd2/BP. The potential application of these heterogeneous systems as catalysts was demonstrated in distinct processes, namely the selective hydrogenation of chloronitrobenzene to chloroaniline and the hydrogen evolution reaction (HER) from acidic medium.