The construction of a heterostructured RGO/g-C3N4/LaCO3OH composite with enhanced visible light photocatalytic activity for MO degradation

Abstract

The construction of a heterojunction and the introduction of a cocatalyst can both promote the transfer of photogenerated electrons, which are effective strategies to enhance photocatalytic efficiency. In this paper, a ternary RGO/g-C₃N₄/LaCO₃OH composite was synthesized by constructing a g-C₃N₄/LaCO₃OH heterojunction and introducing a non-noble metal cocatalyst RGO through hydrothermal reactions. TEM, XRD, XPS, UV-vis diffuse reflectance spectroscopy, photo-electrochemistry and PL tests were carried out to characterize the structures, morphologies and carrier separation efficiencies of products. Benefiting from the boosted visible light absorption capability, reduced charge transfer resistance and facilitated photogenerated carrier separation, the visible light photocatalytic activity of the ternary RGO/g-C₃N₄/LaCO₃OH composite was effectively improved, resulting in a much increased MO (methyl orange) degradation rate of 0.0326 min⁻¹ compared with LaCO₃OH (0.0003 min⁻¹) and g-C₃N₄ (0.0083 min⁻¹). Moreover, by combining the results of the active species trapping experiment with the bandgap structure of each component, the mechanism of the MO photodegradation process was proposed.