On the 2H- to 3C-Type Transformation and Growth Mechanism of SiC Nanowires upon Carbothermal Reduction of Rice Straws

Chang-Ning Huang; Jhong-Yeh Lee; Cheng-Chien Wang

doi:10.1021/acsomega.1c05992

On the 2H- to 3C-Type Transformation and Growth Mechanism of SiC Nanowires upon Carbothermal Reduction of Rice Straws

ACS Omega. 2022 Feb 3;7(6):5039-5052. doi: 10.1021/acsomega.1c05992. eCollection 2022 Feb 15.

Authors

Chang-Ning Huang¹, Jhong-Yeh Lee¹, Cheng-Chien Wang¹

Affiliation

¹ Department of Chemical and Materials Engineering, Southern Taiwan University of Science and Technology, Tainan 710301, Taiwan, R.O.C.

Abstract

SiC nanowires (NWs) and nanoparticles (NPs) fabricated by carbothermal reduction of rice straws with/without FeSi catalysts were characterized by transmission electron microscopy to study the catalyst-facilitated vapor-liquid-solid (VLS) growth against the oriented attachment of the crystals, which underwent 2H- to 3C-type transformation. The cotectic melt of the FeSi catalyst in the Fe-Si-C-O system turned out to promote the VLS growth to form straight and occasionally tapered NWs in contrast to the zigzag ones via the (hkl)-specific coalescence of the faceted NPs. The SiC NWs showed [0001]_2H-directed growth more or less stacked with {111}_3C interlayers following the optimum crystallographic relationship (0001)_2H//{111̅}_3C; [21̅1̅0]_2H//⟨101⟩_3C with zigzag {111}_3C lateral steps and polysynthetic twins/faults near the (0001)_2H/(111)_3C interface. The FeSi-assisted VLS growth and twinning/stacking fault-coupled 2H to 3C phase change may be extended to novel green manufacturing and design of sustainable resources for other semiconductor NWs.