<i>Sargassum</i> Composition and Pre- and Posttreatment Procedures

<p><br></p><p dir="ltr">This supplementary material provides comprehensive information about the composition of various <i>Sargassum</i> species. Additionally, pretreatment procedures including harvesting, washing, drying, grinding, and optional chemical treatments to optimize biomass quality prior to synthesizing carbon materials, and their effect on the <i>Sargassum</i> characteristics are described. Finally, posttreatment methods encompass filtration, washing, drying, and activation processes to enhance carbon material properties are presented. Activation techniques include physical activation using CO₂ or steam, chemical activation with agents like KOH or H₃PO₄, and self-activation utilizing compounds naturally occurring in the biomass. These processes can increase surface areas to over 1000 m²/g and introduce functional groups for enhanced performance. The data describe a systematic approach and support the synthesis methods discussed in the manuscript for converting <i>Sargassum</i> into valuable solid carbon materials.</p>