Improved oxide-ion conductivity of NdBaInO₄by Sr doping

Abstract

The oxide-ion conductivity of NdBaInO 4 has been increased by Sr doping. Nd 0.9 Sr 0.1 BaInO 3.95 showed the highest electrical conductivity among Nd 1Àx Sr x BaInO 4Àx/2 (x ¼ 0.0, 0.1, 0.2, and 0.3). The oxide-ion conductivity s ion of Nd 0.9 Sr 0.1 BaInO 3.95 (s ion ¼ 7.7 Â 10 À4 S cm À1 ) is about 20 times higher than that of NdBaInO 4 (s ion ¼ 3.6 Â 10 À5 S cm À1 ) at 858 C, and the activation energy of oxide-ion conduction is a little lower for Nd 0.9 Sr 0.1 BaInO 3.95 (0.795(10) eV) than that for NdBaInO 4 (0.91(4) eV). The structure analysis based on neutron powder diffraction data revealed that the Sr exists at the Nd site and oxygen vacancies are observed in Nd 0.9 Sr 0.1 BaInO 3.95 . This result indicates that the increase of the oxide-ion conductivity is mainly due to the increase of the carrier concentration. The bond valence-based energy landscape indicated two-dimensional oxide-ion diffusion in the (Nd,Sr) 2 O 3 unit on the bc-plane and a decrease of the energy barrier by the substitution of Nd with Sr cations. † Electronic supplementary information (ESI) available: A document containing the crystallographic data of Nd 0.9 Sr 0.1 BaInO 3.95 , additional experimental information, and a crystallographic information le (CIF) of Nd 0.9 Sr 0.1 BaInO 3.95 . See

Discovery and development of BaNdInO₄ —A brief review—

“…Similar anisotropy was observed in the thermal expansion of lattice parameters of BaNdInO 4 and its solid solutions: ¡ a > ¡ c and ¡ b > ¡ c . 30),45), 56) The electrical conductivities of BaRInO 4 (R = Nd, Er, Y, Sm) were measured in air by a dc 4-probe method (Fig. 6).…”

“…7), and the activation energy for oxide-ion conduction of BaNdInO 4 was 0.91(4) eV. 56) The crystal structure of BaNdInO 4 at 1000°C was analyzed by BaNdInO 4 -type structrure. 30) The lattice parameters a, b and c were higher, while the ¢ angle was lower at 1000°C, compared with those at 20°C.…”

“…¡ of BaNdInO 4 is close to that of yttria stabilized zirconia (YSZ), which is favorable for using this material as a cathode in SOFC applications. The average thermal expansion coefficients of 3 and 8 mol % YSZ between 20 and 1000°C were reported as 1.08 © 10 ¹5 and BaNd 0.9 Sr 0.1 InO 3.95 , 56) Ba 1.1 Nd 0.9 InO 3.95 , 45) BaNd 0.8 Ca 0.2 InO 3.9 , 58) and BaNdIn 0.8 Ti 0.2 O 4.1 . 59) The • ion were measured in reduced atmosphere for BaNdInO 4 , 56) BaNd 0.9 Sr 0.1 InO 3.95 , 56) Ba 1.1 Nd 0.9 InO 3.95 , 45) and BaNd 0.8 Ca 0.2 InO 3.9 .…”

Oxide-ion conduction in the Dion–Jacobson phase CsBi2Ti2NbO10−δ

“…Since the limited structure families restrict further development in chemistry and solid-state ionics, the discovery of oxide-ion conductors with new crystal structures is of vital importance for the development of their applications. Various layered perovskites such as BIMEVOX [18][19][20][21] , the Aurivillius phase [22][23][24] , the Ruddlesden-Popper phase 14,15,[25][26][27][28][29] , the double perovskites [30][31][32] , the brownmillerites 33,34 , the hexagonal perovskite derivative (Ba 3 MoNbO 8.5 ) [35][36][37] , and the BaNdInO 4 -based oxides 16,[38][39][40] were reported to exhibit high oxide-ion conductivities. The Dion-Jacobson phase is an A′/A cation-ordered layered perovskite with a general formula of A′ [A n−1 B n O 3n+1 ] (A′ = Cs, Rb, Li, H, Ag; A = La, Ca, Sr, Bi; and B = Ti, Nb, Ta, etc.…”

“…Here, we have screened 69 Dion-Jacobson phases using available crystallographic data and the bond-valence method (see the details in Supplementary Methods, Supplementary Fig. 1 and Supplementary Table 1) 12,13,16,17,37,38,40,[50][51][52][53] . The chemical composition of CsBi 2 Ti 2 NbO 10 is selected because the bondvalence-based energy barrier for the oxide-ion migration, E b , is relatively low (E b = 0.5 eV) and CsBi 2 Ti 2 NbO 10 does not contain expensive rare-earth elements.…”