Extraction of silicon from rice husk ash

Abstract EN

The use of semiconductor-grade silicon in solar cell fabrication has made solar cells very expensive.

Sources of high purity silicon other than the usual sources, for example, trichlorosilane, silicon tetrachloride, etc.

have been tried for the past decade with the intention of cutting down the cost of solar cell production.

Rice husk has been reported to be a potential source of high purity silicon.

The present study was aimed at producing silicon from ?akistani rice husk and checking its viability as a potential and economical source of high purity silicon.

Silicon was extracted from a rice husk sample and it was found to be of 99.85% purity.

The impurities detected were aluminum, boron, calcium, copper, magne-sium, manganese, and titanium.

Life-time killing impurities (such as vanadium) which affect solar cell efficiency were not detected.

It was also found that that the purity of the extracted silicon could further be increased by repeating the purification processes several times.

In this case, however, the extracted silicon would not be economical.