A hot way to change shape

Nanomaterial Heating cycles are used to transform nanomaterials, but this can often cause shape deformation or particle aggregation. Li et al. show that the addition of strong capping ligands—in this case, polyacrylic acid—can stabilize shapes or help to control final properties during the calcination of β-FeOOH ellipsoidal particles. When heated in air at temperatures of ∼350°C, the particles transformed into porous α-Fe2O3 of similar shape and size, which then could be reduced to form magnetic Fe3O4 particles. The authors also demonstrated that the strong ligand technique worked with β-FeOOH nanorods, Prussian blue nanocubes, cobalt hydroxide nanoplates, and Ni(OH)2 nanoplates. Chem. Mater. 10.1021/acs.chemmater.0c00573 (2020).