Chitosan bimetallic particles with in-situ ROS driven self-cleaning performance for tetracycline elimination

Abstract

Adsorption enrichment coupled with oxidative degradation is a promising technique for eliminating tetracycline (TC) from an aqueous environment. However, the high cost associated with this technique limits its applicability. Thus, in this study, we synthesized Cu2O and CuFe2O4 bimetallic-modified chitosan particles (Cu(I)–CuFe2O4@CS) with high adsorption efficiency and self-cleaning performance. The self-cleaning performance was driven by the in-situ generated reactive oxygen species (ROS). Batch experiments and characterization methods indicated that 97.39% of TC was rapidly adsorbed on the particles surface and subsequently degraded by in-situ generated ROS, to achieve a self-cleaning process. The Cu(I)–CuFe2O4@CS/TC system exhibited maximum O2•- and H2O2 concentration of 12.95 μmol/L and 42.05 μmol/L, respectively. Cu2O was the main source of the ROS generation, while CuFe2O4 effectively adsorbed TC and contributed to the synergistic accumulation of ROS. Moreover, the adsorbed TC with reductive functional properties facilitated the reduction of Fe(III)/Fe(II) and Cu(II)/Cu(I) cycles, thereby improving TC elimination efficiency.