Synthesis and Use in Catalysis of Hematite Nanoparticles Obtained from a Polymer Supported Fe(III) Complex

Abstract Weakly magnetic hematite (α‐Fe 2 O 3 ) nanoparticles were synthesized by heating an amorphous polymer supported iron(III) complex ( Fe_POL ) at 400 °C for 4 h in air. The growth of nanoparticles (NPs) was studied by PXRD, heating the polymer from 150 °C to 400 °C at 25 °C intervals, revealing that, at all temperatures, the only crystalline phase detected is hematite. Conversely, annealing of Fe_POL at 400 °C for 4 h under nitrogen, yielded a material containing wüstite (FeO) as the only crystalline phase, supported onto pyrolised acrylamidic polymer. The synthesized materials were characterized by TXRF, PXRD, SEM‐EDS, XPS, Raman and FTIR spectroscopy as well as by magnetic analysis. Differently from natural micrometric hematite, synthesised nano‐hematite turned out to be an efficient and recyclable catalyst for the hydrogenation of nitroarenes to the corresponding anilines.