Manganese Oxides
Manganese Oxide Films on Au(111)
- Mn deposition on Au(111) in 1×10-6 mbar of oxygen at 300 K
- Annealing at 600 K in 5×10-7mbar O2 to produce oxygen-rich Mn3O4 films
- Vacuum annealing at 800 K to prepare reduced MnO-films
Manganese Oxides
STM overview images of Mn-O films on Au(111):
(100 x 100 nm², 10 pA)
(a)→Oxygen annealed (0.25 ML, UB = 2.7 V)
(b)→Oxygen annealed (2.5 ML (UB = 3.7 V)
(c)→Vacuum annealed (2.5 ML (UB = 3.7 V)
(d)→Vacuum annealed (10 ML UB = 8.7 V
Reduced film: spin-split Mn 2p doublet and Mn2+ satellite at 647 eV ►MnO
Oxidized film: Mn 2p doublet at higher binding energy and increased O 1s signal ►Mn3O4
Atomic patterns on large Mn3O4 crystallites prepared by O2 annealing at 600 K
(a-b) square patterns with 5.8 Ǻ lattice parameter (10×10 nm2)
(c-d) square patterns with 8.2 Ǻ lattice parameter (times √2)
(d-f) line patterns with 12 and 17 Å periodicity (15 x 15 nm2 )
STM conductance spectra measured on Mn3O4 and MnO islands of 9 and 15 Å thickness, respectively
- MnO with plain band gap of 3.2 V (lower curve)
- Mn3O4 with reduced gap size and distinct gap states (upper curves)
- Gap states associated to localized Mn 3d states
For details:
Growth and structural properties of Mn-O thin films on Au(111), Möller, Stavale, Nilius, J. Phys. Chem C 10.1021/ acs.jpcc.8b04176