A non-van der Waals 2D material from natural titanium mineral ore Ilmenite

Abstract

Two-dimensional (2D) materials from naturally occurring minerals are promising and possess interesting physical properties. A new 2D material “Ilmenene” has been exfoliated from the naturally occurring titanate ore ilmenite (FeTiO3) by employing liquid phase exfoliation in a dimethylformamide solvent by ultrasonic bath sonication. Ilmenene displays a [001] orientation that is confirmed by transmission electron microscopy. Probable charge transfer excitation from Fe2+Ti4+ to Fe3+Ti3+ results in ferromagnetic ordering along with the antiferromagnetic phase accompanied by enhanced anisotropy due to surface spins. The 2D nature and band gap states help ilmenene form a heterojunction photocatalyst with titania nanotube arrays, capable of broad spectrum light harvesting and separating/transferring the photogenerated charges effectively for solar photoelectrochemical water splitting.