TY - JOUR
T1 - Photoluminescence Properties of Double Perovskite Tantalates Activated with Mn4+, AE2LaTaO6:Mn4+ (AE = Ca, Sr, and Ba)
AU - Takeda, Yohei
AU - Kato, Hideki
AU - Kobayashi, Makoto
AU - Nozawa, Shunsuke
AU - Kobayashi, Hisayoshi
AU - Kakihana, Masato
N1 - Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/8/31
Y1 - 2017/8/31
N2 - Tetravalent manganese is known as one of the candidate luminous centers to obtain red emission. There are still unclear factors in Mn4+-activated oxide phosphors to achieve intense emission. In this paper, we studied the photoluminescence properties of double perovskite-type tantalates AE2LaTaO6 (AE = Ca, Sr, and Ba) activated with Mn4+. All AE2LaTaO6:Mn exhibited Mn4+-emission in the deep red region under excitation by near-ultraviolet-green light (300-570 nm) at room temperature. Co-substitution of Mg2+, Al3+, and Ti4+ compensates unbalanced charge caused by oxygen defects, resulting in the enhancement of Mn4+-emission. The present cosubstitution effect is different from the usual cosubstitution, such as the replacement of two Al3+ by Mn4+ and Mg2+, taking into consideration the charge balance between cations. Theoretical calculation of band structures based on density functional theory suggests the presence of two kinds of quenching schemes in AE2LaTaO6:Mn, photoionization and electron transfer from valence band to t2g orbitals of Mn.
AB - Tetravalent manganese is known as one of the candidate luminous centers to obtain red emission. There are still unclear factors in Mn4+-activated oxide phosphors to achieve intense emission. In this paper, we studied the photoluminescence properties of double perovskite-type tantalates AE2LaTaO6 (AE = Ca, Sr, and Ba) activated with Mn4+. All AE2LaTaO6:Mn exhibited Mn4+-emission in the deep red region under excitation by near-ultraviolet-green light (300-570 nm) at room temperature. Co-substitution of Mg2+, Al3+, and Ti4+ compensates unbalanced charge caused by oxygen defects, resulting in the enhancement of Mn4+-emission. The present cosubstitution effect is different from the usual cosubstitution, such as the replacement of two Al3+ by Mn4+ and Mg2+, taking into consideration the charge balance between cations. Theoretical calculation of band structures based on density functional theory suggests the presence of two kinds of quenching schemes in AE2LaTaO6:Mn, photoionization and electron transfer from valence band to t2g orbitals of Mn.
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U2 - 10.1021/acs.jpcc.7b06280
DO - 10.1021/acs.jpcc.7b06280
M3 - Article
AN - SCOPUS:85028655525
VL - 121
SP - 18837
EP - 18844
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 34
ER -