DFT+U study of ultrathin α-Fe2O3 nanoribbons from (110) and (104) surfaces

We present a systematic study of the geometric, electronic, and magnetic properties of hematite nanoribbons (α-Fe2O3NRs) using density functional theory. The hematite nanoribbons were generated by cutting atomically thin hematite nanosheets from the (110) and (104) surfaces along their [100] and [010] directions. All nanoribbon types are energetically feasible to synthesize. Nanoribbons obtained from the (110) surface show definite tunable semiconducting character. One type of nanoribbons obtained from the (104) surface shows surface modifications or bending nature indicating pseudo-Jahn-Teller effect, while the other type showed built-in oxygen vacancy on one edge despite preserving the stoichiometry, wherein the built-in oxygen vacancy introduces a half-metallicity into the nanoribbons at larger widths. The results indicate that α-Fe2O3NRs with the appropriate width and type are promising future materials in solar energy conversions and spintronics-based devices.