Incorporation of hierarchical porous MIL-101@MXene into double-network hydrogel for an enhanced strategy for selective and effective removal of hazardous Hg2+ from water


Pang J., Zhu Y., Li M., Xu J., Yuan Z., YÜREKLİ Y., ...Daha Fazla

Separation and Purification Technology, cilt.380, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 380
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1016/j.seppur.2025.135244
  • Dergi Adı: Separation and Purification Technology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, INSPEC
  • Anahtar Kelimeler: Double-network hydrogel, Hierarchical porous, MIL-101, MXene
  • Manisa Celal Bayar Üniversitesi Adresli: Evet

Özet

Hg2+ contamination in aquatic environments represents a significant threat to human health and ecological systems due to its pronounced toxicity and enduring nature. It is imperative to develop a high-performance, recyclable adsorbent for Hg2+ removal to enable effective treatment of wastewater. Herein, MIL-101@MXene was synthesized through in-situ hydrothermal growth of MIL-101 on MXene substrates, and was subsequently incorporated into a double-network hydrogel matrix comprising polyvinyl alcohol (PVA) and chitosan (CS), resulting in the formation of the MIL-101@MXene/hydrogel adsorbent. A comprehensive characterization of MIL-101@MXene/hydrogel was conducted utilizing a series of analytical techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis, and X-ray photoelectron spectroscopy (XPS). The porous hydrogel network of MIL-101@MXene/hydrogel, along with the micro-mesoporous structure of MIL-101@MXene, creates a hierarchical pore architecture. In this configuration, the macropores of the hydrogel facilitate efficient diffusion of Hg2+ into the material's interior while promoting physical adsorption. Meanwhile, the micro-mesopores not only provide a substantial specific surface area but also reveal numerous active adsorption sites, thereby enhancing the overall adsorption capacity. Batch adsorption experiments demonstrated that MIL-101@MXene/hydrogel exhibited optimal performance for the removal of Hg2+ at a pH of 5, achieving a maximum adsorption capacity. In addition, MIL-101@MXene/hydrogel demonstrated competitive selectivity and reusability, with only about a 25 % reduction in Hg2+ adsorption capacity in the presence of various competing ions, and retaining over 55 % of its initial capacity after six successive adsorption-desorption cycles. The adsorption mechanism was further elucidated through FT-IR and XPS analyses conducted both before and after the adsorption process. The results highlighted the coordination of Hg2+ with unsaturated Fe3+ sites and carboxyl oxygen atoms, as well as surface complexation between Hg2+ and the functional groups on MXene. Physisorption also contributed to the overall adsorption process. Additionally, there were interactions characterized by hydrogen bonding and coordination between the hydrogel matrix and Hg2+. This work indicates that MIL-101@MXene/hydrogel is an effective adsorbent with practical potential for Hg2+-contaminated wastewater remediation.