MOF-derived tri-metallic nanoparticle-embedded cellulose aerogels for tetracycline degradation

Abstract

The persistent presence of tetracycline in water poses environmental risks, demanding sustainable remediation. Here, we synthesize MOF-derived tri-metallic nanoparticle–cellulose aerogels for enhanced degradation. By pyrolyzing a trimetallic MOF precursor (Fe/Co/Mn), highly dispersed tri-metallic nitrogen-doped carbon nanoparticles (NCNPs) with synergistic catalytic activity were generated and uniformly embedded within a porous, biodegradable cellulose aerogel matrix. The resulting hybrid aerogel combines the high surface area, porosity, and exceptional adsorption capacity of cellulose with the catalytic prowess of tri-metallic NCNPs, facilitating efficient tetracycline (TC) degradation via peroxymonosulfate (PMS) activation. Structural and morphological characterization (SEM, TEM, XRD, and XPS) confirmed the successful integration of NCNPs and the aerogel's 3D interconnected porous network. The composite demonstrated outstanding TC removal efficiency (99.3 % within 15 min under optimal conditions), owing to enhanced electron transfer and reactive oxygen species (ROS) generation. Mechanistic studies revealed singlet oxygen (¹O₂) as the dominant species, followed by superoxide radicals (O₂^•−), hydroxyl radicals (^•OH), and sulfate radicals (SO₄^•−). The proposed ROS generation and reaction pathway follows the sequence: ¹O₂ > O₂^•− > ^•OH > SO₄^•− highlighting the catalyst's ability to evolve multiple ROS with increasing oxidative selectivity. The aerogel exhibited excellent reusability (92.8 % efficiency after 5 cycles) and minimal metal leaching, underscoring its stability and environmental compatibility. This work showcases MOF-derived tri-metallic catalysts on biopolymer supports as scalable, eco-friendly solutions for antibiotic wastewater treatment.