Abstract One of the challenges that have attracted the attention of governments in recent years is the ability of a country to decontaminate the environment against radioactive release explosions. Performance evaluation of uranium absorption of functionalized GrO@Cu-BTC composite containing ZnO was the goal of this study. Four samples, including GrO@HKUST-N, GrO@HKUST-1, FGrO@HKUST-N and FGrO@HKUST-1, were synthesized by the solvothermal process. X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric (TG/DTG), Fourier transform infrared spectroscopy (FTIR) and N2 absorption techniques were used to monitor the changes in the crystal and the pore structure. The uranium absorption behavior of metal–organic frameworks (MOF) composites was investigated by inductively coupled plasma (ICP) analysis, which included studying the effect of concentration of U, contact time and absorbent amount. The results showed that the presence of FGrO increases the specific area and decreases the diameter of the cavities. The FGrO@HKUST-N composite had a higher BET specific surface area and average pore diameter than the FGrO@HKUST-1, 819.69 m2g− 1 and 1.49 nm, respectively. Also, the FGrO@HKUST-N composite (without ZnO) had the highest adsorbing of U in nuclear solutions due to the carboxyl groups.
