Synthesis of N doped graphene quantum dots-interspersed CdWO₄ heterostructure nanorods as an effective photocatalyst with enhanced photoelectrochemical performance

Herein, N doped graphene quantum dots-interspersed Cadmium tungstate (CdWO₄) nanorods (N-GQDs-CdWO₄) were synthesized via decorating the N-GQDs on the surface of CdWO₄ nanorods in three steps. The morphological and structural properties of the N-GQDs-CdWO₄ nanorods were thoroughly investigated by X-ray diffraction spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier Transform infrared spectroscopy, Raman spectroscopy, and ultraviolet–visible spectroscopy. Based on imaging techniques, it became clear that the N-GQDs decorated on the surface of CdWO₄ nanorods formed a heterostructure. This nanocomposite exhibits enhanced photoelectrochemical performances—more than four times those of bare CdWO₄. In addition, the nanocomposite's photocatalytic activity under ultra-violet light irradiation was almost six fold that of bare CdWO₄. We studied the mechanism governing its exceptional performance. It indicates that the existence of a heterostructure induces a synergistic effect between the N-GQDs and CdWO₄ nanorods that bolsters photoelectric performance. Our work provides a feasible method to synthesize 0D/3D nanocomposites with enhanced photoelectrochemical performances, and offers a solution to rectify current solar energy shortfalls. - Highlights: • For the first time, N-GQDs/CdWO₄ nanorods were obtained by hydrothermal method. • Photocatalytic activities of N-GQDs/CdWO₄ were greatly promoted than CdWO₄. • Mechanism of enhanced activities of N-GQDs/CdWO₄ were deeply investigated.