Classification ntawm Metallic Silicon

Kev faib tawm ntawm cov hlau silicon feem ntau yog ua raws cov ntsiab lus ntawm peb lub ntsiab impurities, hlau, txhuas, thiab calcium, muaj nyob rau hauv cov khoom ntawm hlau silicon. Raws li cov ntsiab lus ntawm cov hlau, txhuas, thiab calcium hauv cov hlau silicon, nws tuaj yeem muab faib ua ntau qib xws li 553, 441, 411, 421, 3303, 3305, 2202, 2502, 1501, 1101, thiab lwm yam.
Hauv kev lag luam, silicon hlau feem ntau yog tsim los ntawm kev txo cov silicon dioxide los ntawm carbon nyob rau hauv lub cub hluav taws xob. Cov tshuaj tiv thaiv kab mob sib npaug yog: SiO2+2C → Si+2CO. Lub purity ntawm silicon ua nyob rau hauv no txoj kev yog 97 ~ 98%, uas yog hu ua metallic silicon. Tom qab melting thiab recrystallizing, impurities raug tshem tawm nrog cov kua qaub kom tau cov hlau silicon nrog purity ntawm 99.7-99.8%.
Cov khoom tseem ceeb ntawm cov hlau nplaum yog silicon, yog li nws muaj cov khoom zoo sib xws rau silicon. Silicon muaj ob allotropes, amorphous silicon thiab crystalline silicon. Amorphous silicon yog cov hmoov dub grey, uas yog cov khoom siv microcrystalline. Crystalline silicon muaj cov qauv siv lead ua thiab cov khoom siv semiconductor ntawm pob zeb diamond, nrog lub melting point ntawm 1410 degree, boiling point ntawm 2355 degree, Mohs hardness ntawm 7, thiab brittleness. Amorphous silicon muaj cov khoom siv tshuaj lom neeg thiab tuaj yeem hlawv hnyav hauv oxygen. Nws reacts nrog cov hlau tsis muaj hlau xws li halogens, nitrogen, thiab carbon ntawm qhov kub thiab txias, thiab tuaj yeem ua rau cov hlau xws li magnesium, calcium, thiab hlau los tsim cov silicides. Amorphous silicon yuav luag insoluble nyob rau hauv tag nrho cov inorganic thiab organic acids, nrog rau hydrofluoric acid, tab sis muaj peev xwm yaj nyob rau hauv sib xyaw acids ntawm nitric acid thiab hydrofluoric acid. Ib qho kev daws teeb meem sodium hydroxide tuaj yeem yaj amorphous silicon thiab tso cov roj hydrogen. Crystalline silicon yog qhov tsis ua haujlwm thiab tsis ua ke nrog oxygen txawm nyob rau qhov kub thiab txias. Nws tsis yog soluble hauv ib qho inorganic lossis organic acid, tab sis tuaj yeem yaj hauv cov kua qaub sib xyaw ntawm nitric acid thiab hydrofluoric acid, nrog rau cov ntsiab lus sodium hydroxide.