TY - JOUR
T1 - Phase Selectivity and Stability in Compositionally Complex Nano (nA1/n)Co2O4
AU - Wang, Xin
AU - Metz, Peter
AU - Calì, Eleonora
AU - Jothi, Palani Raja
AU - Lass, Eric Andrew
AU - Page, Katharine
N1 - Publisher Copyright:
© 2023 American Chemical Society
PY - 2023/9/12
Y1 - 2023/9/12
N2 - A family of compositionally complex spinels with the formula(nA1/n)Co2O4 (A = combinations of Mg, Cr, Mn, Fe, Co, Ni, Cu, and Zn) was synthesized using a low-temperature soft-templating method. The phase selectivity and the temperature stability window for the series were found to depend strongly upon the A-site composition and only modestly on the number of elements (n) present on the A-site. Select control reactions and in situ high-temperature X-ray diffraction (XRD) uncovered a propensity for temperature-activated de-mixing for compositions containing Mg, Ni, Mn, and Fe. The A-site cations exhibit spatially heterogeneous distributions in the as-formed spinels, which diminish with intermediate thermal annealing, as shown by scanning transmission electron microscopy (STEM)/energy dispersive spectroscopy (EDS) and X-ray line profile analysis. The single spinel phases obtained are metastable, separating into a mix of impurity phases and multiple spinel phases with higher temperature annealing. Furthermore, we demonstrate that a “continuous lattice” parameterization of the compositionally complex oxide structure provides a rapid means by which to examine the heterogeneity of the cation distribution through full profile refinement. The demonstrated tunability of the cation distribution or clustering in these compositionally complex spinels via thermodynamic levers affords interesting opportunities for rational design of functional materials.
AB - A family of compositionally complex spinels with the formula(nA1/n)Co2O4 (A = combinations of Mg, Cr, Mn, Fe, Co, Ni, Cu, and Zn) was synthesized using a low-temperature soft-templating method. The phase selectivity and the temperature stability window for the series were found to depend strongly upon the A-site composition and only modestly on the number of elements (n) present on the A-site. Select control reactions and in situ high-temperature X-ray diffraction (XRD) uncovered a propensity for temperature-activated de-mixing for compositions containing Mg, Ni, Mn, and Fe. The A-site cations exhibit spatially heterogeneous distributions in the as-formed spinels, which diminish with intermediate thermal annealing, as shown by scanning transmission electron microscopy (STEM)/energy dispersive spectroscopy (EDS) and X-ray line profile analysis. The single spinel phases obtained are metastable, separating into a mix of impurity phases and multiple spinel phases with higher temperature annealing. Furthermore, we demonstrate that a “continuous lattice” parameterization of the compositionally complex oxide structure provides a rapid means by which to examine the heterogeneity of the cation distribution through full profile refinement. The demonstrated tunability of the cation distribution or clustering in these compositionally complex spinels via thermodynamic levers affords interesting opportunities for rational design of functional materials.
UR - http://www.scopus.com/inward/record.url?scp=85169932474&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.3c01647
DO - 10.1021/acs.chemmater.3c01647
M3 - Article
AN - SCOPUS:85169932474
SN - 0897-4756
VL - 35
SP - 7283
EP - 7291
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 17
ER -