Development and property characterization of sustainable microalgal graphene-like carbon

In carbon manufacturing emerging field, the escalating consumption of fossil fuels and the growing menace of the greenhouse effect have sparked significant interest in the efficient production of high-value carbon, such as graphene (Gr), using renewable biomass resources. This study presents a novel bio-inspired approach to synthesize bio-based graphene (BG) through pyrolysis, using microalgae as a biomass feedstock along with a catalyst. Three microalgae species were selected as raw materials for this process. Through parametric optimizations of the pyrolysis process, Arthrospira platensis (A. platensis) is identified as the optimal biomass feedstock and determines that 600℃ yields biochar with the highest specific surface area (181 m² g^-1). Among the tested catalysts, only CaCl₂·2H₂O facilitates the formation of few-layer BG under 600℃. Increasing the catalyst-to-raw material mass ratio to 3:1 enables the successful synthesis of high-performance, multi-layered, or even local single-layer BG. The pyrolysis kinetic mechanism is analyzed by an Arrhenius model. Additionally, the texture profile analysis is employed to characterize the compressive strength of various carbon. Compared to commercial Gr, BG exhibit superior mechanical properties on machine direction (65.6 % strengthened in longitudinal direction) and enhanced anti-corrosion properties. This research demonstrates the feasibility of synthesizing BG via catalytic pyrolysis utilizing A. platensis as a biomass feedstock and validates their potential applications of mechanical input or ocean equipment surface through texture profile analysis (TPA) of mechanical, as well as, anti-corrosion properties.