Development of New Oxygen Ion Conductors Based on Nd4GeO8 and Nd3GaO6
详细信息 查看全文
- 作者：Ram Dayal Purohit ; Anthony Chesnaud ; Abdessadek Lachgar ; Olivier Joubert ; Maria Teresa Caldes ; Yves Piffard ; and Luc Brohan
- 刊名：Chemistry of Materials
- 出版年：2005
- 出版时间：August 23, 2005
- 年：2005
- 卷：17
- 期：17
- 页码：4479 - 4485
- 全文大小：345K
- 年卷期：v.17,no.17(August 23, 2005)
- ISSN：1520-5002
文摘
New oxygen ion conductors have been prepared by substituting Ga3+ for Ge4+ in Nd4GeO8, Zn2+ andMg2+ for Ga3+ in Nd3GaO6, and Ca2+ and Sr2+ for Nd3+ in Nd3GaO6. A combustion technique usingethylenediamine tetraacetic acid has been developed to synthesize these materials at ~900 
C, leading topowders with spherical particles of about 100-200 nm. The green pellets obtained through the combustion-synthesized powders could be sintered to ~98% at 1250 C. It was found that Nd4Ge1-xGaxO8-x/2 areformed up to x = 0.10, Nd3Ga1-xMxO6-x/2 (M = Zn, Mg) up to x = 0.03, and Nd3(1-x)M'3xGaO6-3x/2 upto x = 0.03 and 0.015 for M' = Ca and Sr, respectively. These relatively small substitution rates inducea significant increase in oxygen ion conductivity (
800C = 0.2 × 10-2 S cm-1 for Nd4Ge0.9Ga0.1O7.95;800C = 0.5 × 10-2 and 0.4 × 10-2 S cm-1 for Nd3Ga0.97M0.03O5.985 with M = Zn and Mg, respectively,and 800C = 0.6 × 10-2 and 0.7 × 10-2 S cm-1 for Nd2.91Ca0.09GaO5.955 and Nd2.955Sr0.045GaO5.9775,respectively) with respect to pure Nd4GeO8 (800C = 2.8 × 10-4 S cm-1) and pure Nd3GaO6 (800C =2.7 × 10-4 S cm-1).
C, leading topowders with spherical particles of about 100-200 nm. The green pellets obtained through the combustion-synthesized powders could be sintered to ~98% at 1250 C. It was found that Nd4Ge1-xGaxO8-x/2 areformed up to x = 0.10, Nd3Ga1-xMxO6-x/2 (M = Zn, Mg) up to x = 0.03, and Nd3(1-x)M'3xGaO6-3x/2 upto x = 0.03 and 0.015 for M' = Ca and Sr, respectively. These relatively small substitution rates inducea significant increase in oxygen ion conductivity (800C = 0.2 × 10-2 S cm-1 for Nd4Ge0.9Ga0.1O7.95;800C = 0.5 × 10-2 and 0.4 × 10-2 S cm-1 for Nd3Ga0.97M0.03O5.985 with M = Zn and Mg, respectively,and 800C = 0.6 × 10-2 and 0.7 × 10-2 S cm-1 for Nd2.91Ca0.09GaO5.955 and Nd2.955Sr0.045GaO5.9775,respectively) with respect to pure Nd4GeO8 (800C = 2.8 × 10-4 S cm-1) and pure Nd3GaO6 (800C =2.7 × 10-4 S cm-1).