Cu-loaded reduced graphene oxide with ultrahigh adsorption performance for tetracycline from aqueous solution

Background: The elimination of antibiotics from wastewater has received extensive academic and social atten-tions since the increasingly antibiotic-related pollution posed fatal threat to aquatic ecosystem and public health. Method: Herein, a high-performance Cu-loaded reduced graphene oxide (C-rGO) was prepared via in-situ for-mation of Cu nanoparticle on graphene oxide (GO), which was subsequently applied to tetracycline (TC) removal. Significant Findings: It was found that compared to the pristine rGO, the TC adsorption capacity of C-rGO was significantly enhanced, which could reach up to a record-high value of 3078 mg g-1. Adsorption kinetics and isotherms for TC onto C-rGO can be well-fitted by pseudo-first order kinetic model and Langmuir model, respectively. The ultrahigh TC adsorption capacity of C-rGO might be attributed to multi-interactions, i.e., pi-pi interaction, cation-pi bonding, surface complexation, electrostatic interaction and hydrogen bond. In addition, the removal efficiency of C-rGO still kept relatively high level after being used for 4 cycles, illustrating outstanding recyclability of C-rGO. And C-rGO showed excellent adsorption capacities for other antibiotics, such as oxytet-racycline, chlortetracycline hydrochloride, ciprofloxacin, sulfamethoxazole and norfloxacin. The ultrahigh TC adsorption ability and outstanding reusability highlighted its great application potential in the field of antibiotic related wastewater treatment.