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Multifunctional magnetic microspheres (Mag@ZnO–Co3O4) with bimetal oxide shell were synthesized via a facile method. The Mag@ZnO–Co3O4 composite was characterized through a vibrating sample magnetometer, N2 adsorption analysis, Fourier transform infrared spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy analyses. The structural analysis showed that the as-prepared microsphere possessed a mean diameter of 150 nm, a bimetal oxide shell thickness of ∼10.0 nm, and a magnetic core, which endowed it with good dispersibility, strong magnetism, and excellent adsorption property for oxytetracycline (OTC). Several experimental conditions, such as solution pH, adsorption time, OTC concentration, and ionic strength were systematically investigated. The Mag@ZnO–Co3O4 composite exhibited a fast adsorption rate, that is, the equilibrium was reached within 90 min, when the concentration of OTC was between 10 and 30 mg/L. The composite showed favorable performance for the adsorption of OTC in the pH range 5–9. According to the adsorption isotherms and kinetics, the removal of OTC was efficient and obeyed the pseudo-second-order rate equation and Langmuir adsorption model.

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Glucose‐derived carbon‐decorated magnetic microspheres were synthesized by an easy hydrothermal carbonization method and used as a high‐efficiency adsorbent to extract bisphenols in water and tea drinks. The as‐prepared carbon‐decorated magnetic microspheres had a well‐defined core–shell structure with a shell thickness of about 5 nm. The microspheres possessed high saturation magnetization at 60.8 emu/g and excellent chemical stability in aqueous solution. The experimental parameters affecting the extraction efficiency, including extraction time, pH, adsorbent dosage, desorption solvents, desorption time, and solution volume were evaluated. Electrostatic and π–π interactions were the major driving forces during extraction. Overall, a new magnetic solid‐phase extraction method of determining bisphenols was developed on the basis of as‐prepared magnetic microspheres. The method had a wide linear range, low limits of detection (0.03–0.10 µg/L), and high recoveries (85.4–104.6%).