One-step synthesis of recycled 3D CeVO4/rGO composite aerogels for efficient degradation of organic dyes

Abstract

Three dimensional (3D) CeVO₄/rGO porous aerogels were fabricated by a one-pot hydrothermal method. The as-prepared aerogels were characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-visible spectroscopy, electrochemical impedance spectroscopy (EIS) and fluorescence spectroscopy (FL) techniques. The results indicated that these aerogels showed a 3D architecture consisting of crosslinked rGO sheets in which CeVO₄ particles were fully embedded. The specific surface area of the hybrid aerogel (143.2 m² g⁻¹) was demonstrated to be 24.3 times higher than that of bare CeVO₄. The photocatalytic activities of the aerogels were investigated through the degradation of methylene blue under visible light irradiation. In comparison with the bare CeVO₄ particles, the CeVO₄/rGO aerogels showed significantly improved photocatalytic efficiency. The enhanced photocatalytic mechanism was mainly due to the synergistic effect between the larger surface area, porous structure of the aerogel and the effective separation of the photo-generated electron–hole pairs. The 3D block structure of lightweight CeVO₄/rGO porous aerogels could not only contribute to their easy separation from the dispersion after photocatalysis, and also to their reuse for practical application.