TEXTURES OF TETRADECAHEDRON DELTA-FEOOH PARTICLES AND THEIR THERMAL-DECOMPOSITION PRODUCTS

delta-FeOOH particles have been prepared by oxidation of Fe(OH)2 with H2O2. The Fe(OH)2 precursors precipitated from a concentrated FeSO4 so lution were aged at different temperatures from 40 to 110-degrees-C. T he delta-FeOOH particles obtained were characterized by scanning elect ron microscopy (SEM), transmission electron microscopy (TEM), X-ray di ffraction (XRD) and N2 adsorption. The delta-FeOOH particles are tetra decahedra and the particle size increases from ca. 0.1 to 1 mum with i ncreasing ageing temperature. The tetradecahedral delta-FeOOH particle s are less crystalline. The N2 adsorption t-plots show the microporous structure of the delta-FeOOH particles obtained by ageing Fe(OH)2 at a higher temperature. The tetradecahedral alpha-Fe2O3 particles formed by outgassing these delta-FeOOH particles above 150-degrees-C have mi cropores with sizes ranging from 0.8 to 2 nm.