Immobilization of α-Fe ₂ O ₃ nanoparticles on the cellulose surface: role of cellulose in tuning the microstructure and crystallographic phase

Abstract: Nanoparticles of α-Fe ₂ O ₃ of diameter ca. 15–130 nm were immobilized on the cellulose fiber surface by a single step in situ hydrothermal method carried out at 150 °C for 16 h. In the absence of cellulose, keeping all other experimental conditions same, nanoflakes of α-FeOOH having width of ca. 25 nm and length of ca. 250 nm were precipitated out. The immobilization of the α-Fe ₂ O ₃ on the cellulose surface owing to the formation of the covalent bond between these two plays an important role in manipulating the nucleation of Fe(III) as α-Fe ₂ O ₃ . The non-existence of the covalent bond leads to the nucleation of the α-FeOOH. A plausible mechanism for the nucleation of α-Fe ₂ O ₃ and α-FeOOH in the presence and absence of cellulose, respectively, has been proposed in the light of the evidence obtained from the FTIR, XPS and ¹³ C CPMAS NMR investigations. Graphical Abstract: [Figure not available: see fulltext.].