Cost-efficient collagen fibrous aerogel cross-linked by Fe (III) /silver nanoparticle complexes for simultaneously degrading antibiotics, eliminating antibiotic-resistant bacteria, and adsorbing heavy metal ions from wastewater

The development of antibacterial and catalytic adsorbents is an ideal strategy to simultaneously remove antibiotics, antibiotic-resistant bacteria, and heavy metal ions from wastewater. Herein, a porous and renewable aerogel was prepared as a lightweight adsorbent by using cost-efficient collagen fibers (CF) from the leather industry. Further, the complexes of Fe 3+ ions with gallic acids modified silver nanoparticles (GA@AgNPs) were selected to sufficiently cross-link the hierarchical CF structure based on coordinated complexation, leading to good mechanical property of the resulted aerogel (AgNPs/Fe@CF). Benefiting from the incorporated AgNPs, AgNPs/Fe@CF aerogel exhibited high antibacterial activity against Tetracycline-resistant E. coli and Methicillin-resistant Staphylococcus aureus. Moreover, the cross-linked AgNPs could accelerate the redox cycle of Fe 3+ /Fe 2+ by facilitating electron transfer and thus enhance the activation of peroxymonosulfate to produce more • OH and SO 4 •− radicals. Therefore, this AgNPs/Fe@CF aerogel demonstrated synergetic Fenton-like catalytic degradation efficiency for 5 different antibiotics (over 90 % within 30 min). In addition, abundant hydroxyl and carboxyl groups on collagen fibers endow desired capacity (greater than70 mg/g) to the porous aerogel, which is able to remove Cr (Ⅵ), Ni (Ⅱ), and Pb (Ⅱ). This study explores a new pathway for the construction of multifunctional aerogel materials for enhancing the purification of wastewater.