The increasing discharge of dye-contaminated wastewater poses a serious threat to aquatic environments, highlighting the urgent need to develop functional advanced materials that move beyond conventional adsorption toward more efficient catalytic degradation of dye pollutants. Inspired by the sustainable concept of valorizing agro-waste, this study developed novel cobalt-doped carbonbased hybrid aerogels for the efficient catalytic activation of peroxymonosulfate (PMS) in the treatment of dye-contaminated water. The aerogel was designed through a bio-derived assembly strategy that integrates Co-doped carbon particles derived from coconut pith as catalytically active building blocks and chitosan as a natural polymeric binder to construct lightweight, porous hybrid aerogels with an extremely low density of 0.010–0.031 g/cm 3 and high porosity of approx. 98%. The Rhodamine B (RhB) degradation efficiency of the as-fabricated aerogels ranged from 83.19% to 99.42% at an initial dye concentration of 25–100 µg/mL within 30 minutes. The study also elucidated the PMS activation and oxidation pathways, identifying singlet oxygen ( 1 O 2 ) as the primary reactive species driving RhB degradation, with hydroxyl radicals (•OH) and sulfate radicals (Formula: see text) playing auxiliary roles. After five cycles of recovery and regeneration, the hybrid aerogels retained excellent stability and reusability. Under the same experimental conditions, the aerogel showed the highest removal efficiency toward congo red (99.92%), followed by RhB (83.19%), whereas methyl orange exhibited the lowest removal efficiency (21.18%). This work highlights a sustainable route that couples advanced water treatment via PMS activation with the value-added conversion of coconut pith into functional carbon-based aerogels.
Do et al. (Fri,) studied this question.