Synthesis and characterization of biomorphic 1D-SiC nanoceramics from novel macroalga precursor material

Abstract

This study reports the first experimental research of Ecklonia radiata macroalga as novel precursor material for the synthesis of one-dimensional Silicon carbide (1D-SiC) Nanoceramics. High-temperature carbothermic reduction of Biosilica (Bio-SiO2) at 1550 °C under controlled Argon purge is proposed as means of facile scalable bulk manufacturing method. The synthesis, characterization, and potential applications of the reaction products are discussed. The experimental results revealed the organic−inorganic hybrid nature of Ecklonia laminae produced micronized powder samples that conveyed key compositional properties. The advantage introduced by this marine biomaterial is the characteristic siliceous structures coupled with high-content of metals and halogenated compounds which mediated the C–SiO heterogeneous reactions under a distinctive in-situ generated gas mixture. Consequently, the biopolymer matrix evolved into a hierarchically porous activated biocarbon of high-surface area (863 m2g-1) which further contributed to the 1D-SiC nanostructures growth via self-catalytic (VSL) mechanisms. Two high-aspect ratio distinctive morphologies were identified ─Nanowires and Nanorods─ with respective diffraction phases assigned 3C–SiC and 6H–SiC (1:4). Since Bio-SiO2 based materials are a new-generation of engineered materials of high-interest it is concluded Ecklonia radiata as novel sustainable source of Bio-SiO2, demonstrated excellent characteristics yielding valuable outputs. The innovative approach of this proposal is based in the utilization of macroalgae biomass via unconventional routes targeting the advancement and the cleaner production of biomorphic 1D-SiC Nanoceramics, with special emphasis on future sustainable scenarios under a blue economy scheme.