Highly ordered Ge-incorporated akaganeite (β-FeOOH): a tunnel-type nanorod

Abstract

A highly ordered Ge-incorporated akaganeite with the atomic ratio of Ge/Fe = 0.14 and Cl/Fe = 0.11 was firstly synthesized through hydrolysis and acidification of a mixed solution of FeCl₃·6H₂O and TEOGe (Ge(OC₂H₅)₄) under the α-Fe₂O₃ synthesis conditions. The newly synthesized Ge-akaganeite shows a monodisperse nanorod with 15–17 nm in width and ∼200 nm in length, the distinctly enhanced structural ordering and stability, and substantial differences in crystallographic and magnetic features. Here we propose a hypothetical akaganeite model with Ge occupying the tunnel sites as Ge(OH)₄⁰ based on crystallographic and chemical analyses.