Cathode material of solid oxide fuel cell and preparation and application thereof

Abstract

The invention discloses a cathode material of a solid oxide fuel cell and a preparation method thereof. The cathode material is characterized in that the cathode material is a composite negative electrode formed by a perovskite oxide and an oxide MO2 modified on the surface of the perovskite oxide, wherein M is Ti, Zr, Nb, Ce, Ru or Sn, the mass content of the oxide MO2 in the composite negative electrode accounts for 1-20%, the particle size of the oxide MO2 is 0.5 to 100 nanometers, and the oxide MO2 in the composite negative electrode coats the surface of the perovskite oxide. The perovskite oxide can be first prepared on the surface of an electrolyte or a partition layer of the battery by methods of coating, silk-screen printing, flow casting and the like, and then the oxide MO2 is modified on the surface of the perovskite oxide in the negative electrode by methods of solution impregnation, sol impregnation, magnetron sputtering and the like. The cathode material disclosed by the invention is endowed with excellent electrochemical performance and favorable stability.

Description

technical field

[0001] The invention relates to the field of fuel cells, in particular to a solid oxide fuel cell cathode material with good stability and performance and a preparation method thereof. Background technique

[0002] Solid Oxide Fuel Cell (SOFC) can convert the chemical energy of fuel into electrical energy through electrochemical reaction at high temperature. It has the characteristics of flexible fuel, high power generation efficiency, and environmental friendliness. It is regarded as the most advanced in the 21st century. One of the energy conversion technologies.

[0003] Perovskite oxide is a commonly used cathode material for solid oxide fuel cells, with ABO 3 Structure, the A site is usually a rare earth or alkaline earth element, and the B site is usually a transition metal element of Group VIIIB in the fourth period. Strontium-doped lanthanum manganite (LSM) is a typical high-temperature SOFC cathode material with good stability, but its catalytic ac...

Examples

Embodiment 1

[0018] La 0.6 Sr 0.4 CoO 3-δ (LSC)—TiO 2 Composite cathode and its preparation. Using Ni-YSZ (mass ratio 1:1) as the anode, YSZ as the electrolyte, and GDC as the separator, an anode-supported battery assembly was prepared. Preparation of La by the citric acid method 0.6 Sr 0.4 CoO 3-δ (LSC) was calcined at 1000°C for 2 h to obtain a powder. The powder (0.5 g) was thoroughly ground and an appropriate amount of binder (n-butanol, 0.5 g) was added to prepare a slurry. Coating LSC (0.012g) slurry (area: 0.5cm 2 ) to the separator of the anode-supported battery assembly, and baked at 1050°C for 3h. Using butyl titanate as the titanium source and ethanol as the solvent, prepare a 0.25mol / L butyl titanate solution, impregnate the butyl titanate solution into the LSC cathode, and bake it at 600°C for 1 hour to obtain a composite cathode. Among them, TiO 2 The particle size is 10-30 nm, TiO 2 The mass content in the cathode is 2.5%.

[0019] On the anode side, humidified h...

Embodiment 2

[0021] La 0.6 Sr 0.4 co 0.2 Fe 0.8 o 3-δ (LSCF)—ZrO 2 Cathode and its preparation: Ni-YSZ (mass ratio 1:1) was used as the anode, YSZ was used as the electrolyte, and GDC was used as the separator to prepare an anode-supported battery assembly. Preparation of La by the citric acid method 0.6 Sr 0.4 co 0.2 Fe 0.8 o 3-δ Calcined at 1000° C. for 2 hours to obtain a powder, which was thoroughly ground (0.5 g) and added with an appropriate amount of binder (n-butanol, 0.5 g) to prepare a slurry. Coating LSCF (0.012g) slurry (area: 0.5cm 2 ) to the separator of the anode-supported battery assembly, and baked at 1050°C for 3h. Using zirconium nitrate as zirconium source and water as solvent, prepare 0.5mol / L zirconium nitrate solution, impregnate the zirconium nitrate solution into the LSCF cathode, and bake at 700°C for 2h to obtain the composite cathode. Among them, ZrO 2 The particle size is 30-50 nm, ZrO 2 The mass content in the cathode is 5%.

[0022] On the anod...

Embodiment 3

[0024] Ba 0.6 Sr 0.4 co 0.2 Fe 0.8 o 3-δ (BSCF)—CeO 2 Cathode preparation: Ni-YSZ (mass ratio 1:1) was used as the anode, YSZ was used as the electrolyte, and GDC was used as the separator to prepare an anode-supported battery assembly. Preparation of Ba by the citric acid method 0.6 Sr 0.4 co 0.2 Fe 0.8 o 3-δCalcined at 1000° C. for 2 hours to obtain a powder, which was thoroughly ground (0.5 g) and added with an appropriate amount of binder (n-butanol, 0.5 g) to prepare a slurry. Coating BSCF (0.012g) slurry (area: 0.5cm 2 ) to the separator of the anode-supported battery assembly, and baked at 1050°C for 3h. With cerium nitrate Ce(NO 3 ) 3 ·6H 2 O is the cerium source, water is the solvent, and ammonium citrate is the complexing agent. Prepare 0.5mol / L cerium nitrate sol (the molar ratio of metal ion to ammonium citrate is 1:1), and impregnate the cerium nitrate sol into the BSCF cathode , and fired at 600°C for 2h to obtain a composite cathode. Among them, ...

technical field

[0001] The invention relates to the field of fuel cells, in particular to a solid oxide fuel cell cathode material with good stability and performance and a preparation method thereof. Background technique

[0002] Solid Oxide Fuel Cell (SOFC) can convert the chemical energy of fuel into electrical energy through electrochemical reaction at high temperature. It has the characteristics of flexible fuel, high power generation efficiency, and environmental friendliness. It is regarded as the most advanced in the 21st century. One of the energy conversion technologies.

[0003] Perovskite oxide is a commonly used cathode material for solid oxide fuel cells, with ABO 3 Structure, the A site is usually a rare earth or alkaline earth element, and the B site is usually a transition metal element of Group VIIIB in the fourth period. Strontium-doped lanthanum manganite (LSM) is a typical high-temperature SOFC cathode material with good stability, but its catalytic ac...

Examples

Embodiment 1

[0018] La 0.6 Sr 0.4 CoO 3-δ (LSC)—TiO 2 Composite cathode and its preparation. Using Ni-YSZ (mass ratio 1:1) as the anode, YSZ as the electrolyte, and GDC as the separator, an anode-supported battery assembly was prepared. Preparation of La by the citric acid method 0.6 Sr 0.4 CoO 3-δ (LSC) was calcined at 1000°C for 2 h to obtain a powder. The powder (0.5 g) was thoroughly ground and an appropriate amount of binder (n-butanol, 0.5 g) was added to prepare a slurry. Coating LSC (0.012g) slurry (area: 0.5cm 2 ) to the separator of the anode-supported battery assembly, and baked at 1050°C for 3h. Using butyl titanate as the titanium source and ethanol as the solvent, prepare a 0.25mol / L butyl titanate solution, impregnate the butyl titanate solution into the LSC cathode, and bake it at 600°C for 1 hour to obtain a composite cathode. Among them, TiO 2 The particle size is 10-30 nm, TiO 2 The mass content in the cathode is 2.5%.

[0019] On the anode side, humidified h...

Embodiment 2

[0021] La 0.6 Sr 0.4 co 0.2 Fe 0.8 o 3-δ (LSCF)—ZrO 2 Cathode and its preparation: Ni-YSZ (mass ratio 1:1) was used as the anode, YSZ was used as the electrolyte, and GDC was used as the separator to prepare an anode-supported battery assembly. Preparation of La by the citric acid method 0.6 Sr 0.4 co 0.2 Fe 0.8 o 3-δ Calcined at 1000° C. for 2 hours to obtain a powder, which was thoroughly ground (0.5 g) and added with an appropriate amount of binder (n-butanol, 0.5 g) to prepare a slurry. Coating LSCF (0.012g) slurry (area: 0.5cm 2 ) to the separator of the anode-supported battery assembly, and baked at 1050°C for 3h. Using zirconium nitrate as zirconium source and water as solvent, prepare 0.5mol / L zirconium nitrate solution, impregnate the zirconium nitrate solution into the LSCF cathode, and bake at 700°C for 2h to obtain the composite cathode. Among them, ZrO 2 The particle size is 30-50 nm, ZrO 2 The mass content in the cathode is 5%.

[0022] On the anod...

Embodiment 3

[0024] Ba 0.6 Sr 0.4 co 0.2 Fe 0.8 o 3-δ (BSCF)—CeO 2 Cathode preparation: Ni-YSZ (mass ratio 1:1) was used as the anode, YSZ was used as the electrolyte, and GDC was used as the separator to prepare an anode-supported battery assembly. Preparation of Ba by the citric acid method 0.6 Sr 0.4 co 0.2 Fe 0.8 o 3-δCalcined at 1000° C. for 2 hours to obtain a powder, which was thoroughly ground (0.5 g) and added with an appropriate amount of binder (n-butanol, 0.5 g) to prepare a slurry. Coating BSCF (0.012g) slurry (area: 0.5cm 2 ) to the separator of the anode-supported battery assembly, and baked at 1050°C for 3h. With cerium nitrate Ce(NO 3 ) 3 ·6H 2 O is the cerium source, water is the solvent, and ammonium citrate is the complexing agent. Prepare 0.5mol / L cerium nitrate sol (the molar ratio of metal ion to ammonium citrate is 1:1), and impregnate the cerium nitrate sol into the BSCF cathode , and fired at 600°C for 2h to obtain a composite cathode. Among them, ...