Detection and adsorption of cefixime and methylene blue in aqueous solution by using hydroxyl-functionalized MOF nanostructure MIL-101

Abstract

MIL-101-OH, a hydroxyl-functionalized metal–organic framework (MOF), was synthesized as a nanostructured adsorbent to detect and eliminate methylene blue (MB) and cefixime (CEF) from aqueous solutions. To improve its interaction with pollutants, MIL-101 was post-synthetically modified with hydroxyl group. BET analysis showed a specific surface area of 1367 m2/g, and FTIR and XRD analyses verified the structural integrity and successful functionalization. The uniform distribution of particle sizes was shown by SEM imaging. To enable detection based on changes in the refractive index, the functionalized MOF was also used as a coating material on an optical fiber sensor. CEF and MB had maximum adsorption capacities of 328 mg/g and 358 mg/g, respectively. The results demonstrate the potential of MIL-101-OH for simultaneous adsorption and optical sensing applications in water treatment. The sensor demonstrated a linear dynamic range of 0–10 mg/L with response times of 75and 32 s for CEF and MB, respectively. © 2025 Elsevier B.V.