Product Name: Lanthanum disilicide (LaSi2)

Specification: 0.8-10um (D50)

Shape: irregular

Color: Black gray

Features: High resistivity, low coefficient of thermal expansion, excellent thermal stability

Applications: Electric heating equipment, ‌ high temperature sensor, high temperature resistant ceramic materials, high temperature tools and thermal conductivity materials and other fields

Lanthanum disilicide 

chemical formula: LaSi2 

Molecular weight: 195.0765 

CAS login number: 12056-90-5 

EINECS login number: 235-017-4 

Density (g/mL, 25 ℃): 5.0 

Properties and stability: The resistivity is higher than that of the corresponding metal, and the temperature coefficient of resistance is positive, but becomes negative at 500 ℃. Easy to reactwith hydrochloric acid and hydrofluoric acid. 

synthetic method  

1) Mix elemental Si and metal lanthanum powder in proportion, compact them, and melt them in vacuum to obtain. 

2) The mixture of La, Si, and Hg is heated in a quartz tube using an electric furnace at a temperature of approximately 450 ℃ for 10-12 hours. Excess mercury is distilled using a bent tube. After the mercury is collected at the cold end of the tube, the product is annealed at 450-600 ℃ at the hot end of the tube. 

Application areas: 

1. Thermoelectric materials: Lanthanum silicide has high electrical conductivity and low thermal conductivity, meeting the standards of high-quality thermoelectric materials (high ZT value), and can directly convert waste heat into electrical energy. 

-Industrial waste heat recovery systems (such as power plants, steel plants). 

-Radioisotope thermoelectric generator (RTG) for deep space probes. 

2. Electronic devices: metal semiconductor transition characteristics, low resistivity. 

-Integrated circuit: used as a connecting material or diffusion barrier, especially in high-temperature electronic devices. 

-Thin film technology: used for preparing transparent conductive thin films (such as touch screens, solar cell electrodes). 

3. Catalytic field: The d-orbital electrons and surface active sites of La can promote the reaction. 

-Methane reforming for hydrogen production: LaSi ₂ - based catalysts exhibit stability at high temperatures. 

-Automotive exhaust treatment: As an additive for ternary catalysts, it improves the efficiency of NO ₓ reduction. 

4. High temperature structural materials: high melting point (>1500 ℃), oxidation resistance. 

-Coating for aircraft engine turbine blades. 

-High temperature resistant components of nuclear reactors (such as cladding materials). 

5. Hydrogen storage material: The hydrogen absorption ability of La combined with the stable structure of silicon may form a reversible hydrogen storage system. 

6. Coatings and composite materials: resistant to high temperature oxidation and corrosion. 

-Protective coating on the surface of metal substrates (such as titanium alloys). 

-Composite with silicon carbide to enhance the fracture toughness of ceramic materials. 

Storage method: This product should be sealed and stored in a dry and cool environment. It should not be exposed to air for a long time to prevent moisture from causing aggregation, affecting dispersion performance and usage effect. In addition, it should be avoided from heavy pressure and not in contact with oxidants. It should be transported as ordinary goods.