Nonstoichiometric Disorder in Single Crystalline MnO

Abstract

The electrical conductivity of single crystalline manganous oxide was investigated over the temperature range of 900°–1150°C while in thermodynamic equilibrium with oxygen partial pressures of 10−6–10−21 atm. Results indicated that normalMnO may be either p‐ or n‐type. Slopes of 1/6 and −1/6 are obtained from the log σ vs. log PO2 data for the p‐ and n‐type regions, respectively. Thermogravimetric measurements at thermodynamic equilibrium support the evidence of the electron mobility being much greater than that for electron holes in normalMnO . The enthalpies of formation of nonstoichiometric disorder and activated enthalpy of movement of electron holes in p‐type normalMnO were determined to be −18 and 12 kcal/mole, respectively. The bandgap of normalMnO was calculated from the minima of the log σ vs. log PO2 data to be 52.8 kcal/mole (2.3 eV).

Size-dependent Lattice Contraction and Oxidation State Ratio in Nano-MnO: Potential Tunable Biomedical Applications

“…Additionally, conduction in MnO is electronic, with holes dominating at high oxygen activities and electrons dominating at low oxygen activities [68], [70]. Though further studies will need to be completed to explore the dominant point defects that occur specifically in MnO nanocrystals, the following discussion explores point defect balance via Kroger-Vink notation.…”

Kirkendall Void Formation During Selective Oxidation

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