SiO2/Ga2O3 nanocomposite for highly efficient selective removal of cationic organic pollutant via synergistic electrostatic adsorption and photocatalysis

To effectively and selectively remove the cationic organic pollutant from wastewater, SiO2/Ga2O3 composite samples were synthesized via a facile electrospinning method. The obtained composite exhibited a superior removal efficiency for cationic rhodamine B (RhB) dye and methylene blue (MB) dye compared with Ga2O3, resulting from the variation of surface charge property of composite and the improvement of the separation efficiency of photogenerated electron-hole pairs. Under the synergistic effect of electrostatic adsorption and photocatalysis, more than 95% of RhB and MB dyes were removed after irradiation with the Xe lamp for 30 min. The selective removal mechanism of cationic dye was studied by testing the adsorption property, zeta potential and photoluminescence (PL) spectra of the synthesized samples. This study provides a novel and effective approach to the synthesis of high-performance remover for cationic dye based on Ga2O3 nanomaterials.