Nanoarchitectonics of poly(vinyl alcohol)/graphene oxide composite electrodes for highly efficient electrosorptive removal of U(VI) from aqueous solution

The radioactive pollution attributed to the discharge of uranium-containing wastewater is considered as a longterm threat to the ecological environment. Herein the nanoarchitectonics of poly (vinyl alcohol)/graphene oxide composite (PVA/GO) electrodes were performed for the efficient U(VI) electrosorption from aqueous solution. The cyclic voltammetry (CV) measurements were conducted to evaluate the capacitive characteristics of the PVA/GO electrodes. The electrosorption capability of U(VI) was significantly enhanced by electrosorption using PVA/GO electrodes. The PVA: GO mass ratios for the PVA/GO composite electrodes were optimized according to their electrosorption performance, which showed PVA/GO-4 was the best among them owing to its excellent conductivity and well-developed mesoporous structure. The electrosorption data were simulated by different models, suggesting the good-fitting of Langmuir model for the isotherms and the first-order model for the kinetics. The electrosorption capacity of U(VI) reaches 333.0 mg/g at 0.9 V. The U(VI) electrosorption mechanism related to electrical double-layer attraction and complexation was clarified by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Moreover, the electrosorption-desorption cycles suggested excellent regeneration This works highlights the promising application of PVA/GO electrodes for the efficient electrosorptive removal/separation of U(VI) from radioactive wastewater.

Automated summary

The study focuses on the efficient electrosorption of U(VI) from uranium-containing wastewater using polyvinyl alcohol/graphene oxide composite electrodes, with PVA/GO-4 showing the best performance. The Langmuir model and first-order model are suitable for predicting the adsorption behavior, with U(VI) reaching a capacity of 333.0 mg/g at 0.9 V. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) confirm the electrosorption mechanism.