As a typical rare earth composite oxide, lanthanum cerium oxide has the following core properties:
- Oxygen storage capacity: Ce4+Reduction releases lattice oxygen (oxygen diffusion coefficient at 600°C> 10-8cm2/s)
- Ionic conductivity: >01 S/cm at 800°C (fuel cell electrolyte material)
- Photoresponsiveness: strong absorption in the ultraviolet region (bandgap ≈ 3.2 eV), visible light catalytic activity
Chemical Properties:
- Redox: Ce4+/Ce3+Reversible conversion (oxygen storage capacity> 500 μmol O2/g)
- Acidity and alkalinity: the surface is weakly alkaline (isoelectric point pH≈8.5)
- Thermal stability: stable to 1400°C in air (phase separation may occur at high temperatures)
- Defect characteristics: low oxygen vacancy formation energy (5-1.2 eV)
Applications:
Environmental catalysis
- Automobile exhaust purification: a key component of three-way catalyst (TWC), CO conversion rate > 95%@400°C
- VOCs treatment: toluene is completely oxidized at a higher temperature than pure CeO2Reduce by 50-80°C
- SOx/NOxRemoval: Sulfur tolerance is better than pure cerium-based materials
Energy Materials
- Solid oxide fuel cells: electrolyte material (800°C power density> 5 W/cm2)
- Hydrogen production catalyst: Selectivity > 90% for hydrogen production by ethanol steam reforming
- Solar thermochemical cycle: a two-step water splitting to produce hydrogen materials
Functional materials
- Chemical Mechanical Polishing: IC Copper Interconnect CMP Paste (Surface Roughness<5nm)
- UV shielding agent: sunscreen cosmetic additive (UV-A zone absorption rate > 95%)
- Gas Sensor: CO2The sensitivity of the sensor is 3-5 times higher than that of conventional materials