20.500.12556/RUL-188120 From waste to catalyst cobalt-functionalized silica as a photocatalyst for water purification The repurposing of waste industrial materials for use in environmental remediation is of great interest in terms of the circular economy as well as public health and safety efforts. Herein, an innovative approach is presented to synthesize a cobalt-functionalized waste silica (Co-MS) utilizing a green, solvent-deficient method (SDM), using industrial waste micron-sized silica (MS) as a sustainable support material. The resulting Co-MS composite is evaluated as a photocatalyst for the removal of methylene blue (MB) under natural sunlight, offering an energy-efficient and environmentally friendly treatment method. Comprehensive characterization confirmed the formation of multiple-valence-state cobalt nanoparticles─Co, CoO, and Co$_3$O$_4$ on the waste silica support. The resulting optimal composite includes 9.1 wt % cobalt oxide species and shows a polyoxide nature with finely dispersed cobalt oxide nanoparticles that are less aggregated compared to bulk Co$_3$O$_4$ and show an improved photocatalytic performance under solar light. Incorporation of cobalt oxide species into MS also results in an SBET increase from 43 m$^2$ g$^{–1}$ for bulk Co$_3$O$_4$ to 91 m$^2$ g$^{–1}$ for the Co-MS composite. The selected composite Co-MS thus achieves 87.5% MB removal efficiency within 1 h, demonstrating its potential as a low-cost, sustainable photocatalyst for wastewater treatment applications. green chemistry novel photocatalyst water purification photocatalysis zelena kemija nov fotokatalizator čiščenje vode fotokataliza true false true Angleški jezik Slovenski jezik Članek v reviji 2026-09-18 12:28:09 2026-09-18 12:28:10 2026-09-19 04:30:09 0000-00-00 00:00:00 2026 0 0 Str. 43203-43214 iss. 29 Vol. 11 28 Jul. 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 544.526.5 2470-1343 10.1021/acsomega.6c00378 286112259 RAZ_Zeljkovic_Sasa_2026.pdf RAZ_Zeljkovic_Sasa_2026.pdf 1 AF2CE9B20E4D76327B2758632A7A5649 6b12a4b2265be20bef1b0506f6864b590afe235fd53054247439e3cfd497a253 1df26c44-b34c-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=248140 https://pubs.acs.org/acsodf/article/doi/10.1021/acsomega.6c00378/5214557/From-Waste-to-Catalyst-Cobalt-Functionalized 1 9a2d245f-b34b-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=248137 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0