Fig. 1. Morphologic structures of graphene oxide (GO) and rGO/BB hydrogel

Fig. 2. Schematic of a three-dimensional electrode experimental device1‒DC power supply, 2‒Graphite plate, 3‒Particle electrode

Fig. 3. Effects of electrolyte concentration on the adsorption of uranyl carbonate

Fig. 4. Effects of applied voltage on the adsorption of uranyl carbonate

Fig. 5. Effects of plate spacing on the adsorption of uranyl carbonate

Fig. 6. Effects of solution pH value on the adsorption of uranyl carbonate

Fig. 7. Effects of particle electrode dosage on the adsorption of uranyl carbonate

Fig. 8. Efficiency differences between electrochemical and physicochemical adsorption

Fig. 9. Effects of initial uranium concentration and adsorption time on the adsorption of uranyl carbonate

Fig. 10. (a) SEM spectra of rGO/BB and rGO/BB-U hydrogel particles, (b) elemental spectra of U, C, N, O, and Cl on the surfaces of rGO/BB-U hydrogel particles, and (c) map spectra of rGO/BB-U hydrogel particles

Fig. 11. (a) Raman spectra of RPrGO/BB and rGO/BB hydrogel particles, (b) FT-IR spectra of BB, GO, rGO/BB, and rGO/BB-U particles

Fig. 12. XPS spectra (a), spectrogram of U 4f (b), C 1s (c) and O 1s (d) before and after adsorption of uranium by rGO/BB hydrogel particles

Fig. 13. (a) Adsorption elution of three-dimensional electrochemical electrodes, (b) SEM spectra after particle electrode elution, and (c) map spectra after particle electrode elution