TY - JOUR
T1 - Property and cation valence engineering in entropy-stabilized oxide thin films
AU - Kotsonis, George N.
AU - Meisenheimer, Peter B.
AU - Miao, Leixin
AU - Roth, Joseph
AU - Wang, Baomin
AU - Shafer, Padraic
AU - Engel-Herbert, Roman
AU - Alem, Nasim
AU - Heron, John T.
AU - Rost, Christina M.
AU - Maria, Jon Paul
N1 - Funding Information:
G.N.K. and J-P.M. gratefully acknowledge support from NSF ceramics Awards No. DMR-1610844 and No.DMR-1839087. P.B.M. and J.T.H. are supported by NSF Grant No. DMR-1847847. The work of L.M. and N.A. was supported by the Penn State Center for Nanoscale Sciences, an NSF MRSEC under Grant No. DMR-1420620. J.R. acknowledges support from the NSF Graduate Research Fellowship Program under Grant No. DGE1255832. G.N.K., P.B.M., L.M., J.R., R.E-H., N.A., J.T.H., C.M.R., and J-P.M. also gratefully acknowledge support from NSF MRSEC DMR-2011839. This research used resources of the Advanced Light Source, a U.S. DOE Office of Science User Facility under Contract No. DE-AC02-05CH11231.
Publisher Copyright:
© 2020 American Physical Society.
PY - 2020/10/19
Y1 - 2020/10/19
N2 - We present data for epitaxial thin films of the prototypical entropy-stabilized oxide (ESO), Mg0.2Ni0.2Co0.2Cu0.2Zn0.2O, that reveals a systematic trend in lattice parameter and properties as a function of substrate temperature during film growth with negligible changes in microstructure. A larger net Co valence in films grown at substrate temperatures below 350 °C results in a smaller lattice parameter, a smaller optical band gap, and stronger magnetic exchange bias. Observation of this phenomena suggests a complex interplay between thermodynamics and kinetics during ESO synthesis; specifically thermal history, oxygen chemical potential, and entropy. In addition to the compositional degrees of freedom available to ESO systems, subtle nuances in atomic structure at constant metallic element proportions can strongly influence properties, simultaneously complicating physical characterization and providing opportunities for property tuning and development.
AB - We present data for epitaxial thin films of the prototypical entropy-stabilized oxide (ESO), Mg0.2Ni0.2Co0.2Cu0.2Zn0.2O, that reveals a systematic trend in lattice parameter and properties as a function of substrate temperature during film growth with negligible changes in microstructure. A larger net Co valence in films grown at substrate temperatures below 350 °C results in a smaller lattice parameter, a smaller optical band gap, and stronger magnetic exchange bias. Observation of this phenomena suggests a complex interplay between thermodynamics and kinetics during ESO synthesis; specifically thermal history, oxygen chemical potential, and entropy. In addition to the compositional degrees of freedom available to ESO systems, subtle nuances in atomic structure at constant metallic element proportions can strongly influence properties, simultaneously complicating physical characterization and providing opportunities for property tuning and development.
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U2 - 10.1103/PhysRevMaterials.4.100401
DO - 10.1103/PhysRevMaterials.4.100401
M3 - Article
AN - SCOPUS:85095420724
SN - 2475-9953
VL - 4
JO - Physical Review Materials
JF - Physical Review Materials
IS - 10
M1 - 100401
ER -