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Ultrafast carbothermal reduction of silica to silicon using a CO₂ laser beam.

ABSTRACT: We report the extraction of silicon via a carbothermal reduction process using a CO₂ laser beam as a heat source. The surface of a mixture of silica and carbon black powder became brown after laser beam irradiation for a few tens of seconds, and clear peaks of crystalline silicon were observed by Raman shift measurements, confirming the successful carbothermal reduction of silica. The influence of process parameters, including the laser beam intensity, radiation time, nitrogen gas flow in a reaction chamber, and the molar ratios of silica/carbon black of the mixture, on the carbothermal reduction process is explained in detail.

SUBMITTER: Maeng SH

PROVIDER: S-EPMC7729951 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Ultrafast carbothermal reduction of silica to silicon using a CO2 laser beam.

Maeng Seok-Ho SH Lee Hakju H Park Min Soo MS Park Suhyun S Jeong Jaeki J Kim Seongbeom S

Scientific reports 20201210 1

We report the extraction of silicon via a carbothermal reduction process using a CO2 laser beam as a heat source. The surface of a mixture of silica and carbon black powder became brown after laser beam irradiation for a few tens of seconds, and clear peaks of crystalline silicon were observed by Raman shift measurements, confirming the successful carbothermal reduction of silica. The influence of process parameters, including the laser beam intensity, radiation time, nitrogen gas flo ...[more]

PMID: 33303838

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