Reduction of haematite to magnetite induced by hydrogen ion implantation

Microstructural changes induced by hydrogen ion implantation in haematite ( ) have been investigated by transmission electron microscopy. It has been found that the hydrogen ion implantation causes the haematite magnetite ( ) reduction at room temperature. From electron diffraction patterns after the hydrogen implantation, the following orientation relationship was found to exist between haematite and magnetite: . Since these results agree with those in previous studies, microstructural changes during the reduction were obtained by using the implantation technique. The reduction mechanism of magnetite from haematite is discussed in terms of the experimental results on crystallographic relationships.