The nature and preparation method of elemental silicon

1.

The elemental silicon crystal has a diamond-shaped structure, is gray-black, has a high hardness and a high melting point, and is an important material for the electronics industry

Silicon chemistry is a high-temperature chemistry and is inactive at room temperature.

Si+2F ₂ =SiF ₄

At room temperature, silicon and strong alkali solution react extremely slowly

+ 4OH si ^- = SiOF _.

At room temperature, Si is dissolved in a mixed acid of HF-HNO ₃ to generate H ₂ SiF ₆

3Si+18HF+4HNO ₃ =3H ₂ SiF ₆ +4NO+8H ₂ O

At high temperatures, silicon is more active and can be combined with many elemental substances, and heating can also promote hydrofluoric acid to dissolve silicon elemental substances

2.

Reducing SiO ₂ with C at high temperature can obtain crude elemental silicon

SiO ₂ +2C=Si+2CO

The crude elemental silicon reacts with Cl ₂ to transform into liquid SiCl ₄

Si+2C1 ₂ =SiCl ₄

After rectification, SiCl ₄ can be reduced with active metal or H ₂ to obtain high-purity elemental silicon

SiCl ₄ +2Zn=Si+2ZnCl ₂

SiCl ₄ +2H ₂ =Si+4HCl