The photocatalytic properties of hollow (GaN)1-x(ZnO)x composite nanofibers synthesized by electrospinning

(GaN) 1-x (ZnO) x composite nanofibers with hollow structure were prepared by initial electrospinning, and the subsequent calcination and nitridation. The structure and morphology characteristics of samples were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). The characterization results showed the phase transition from ZnGa 2 O 4 to (GaN) 1-x (ZnO) x solid-solution under ammonia atmosphere. The preparation conditions were explored and the optimum nitridation temperature and holding time are 750   °C and 2   h, respectively. The photocatalytic properties of (GaN) 1-x (ZnO) x with different Ga:Zn atomic ratios were investigated by degrading Rhodamine B under the visible light irradiation. The photocatalytic activity sequence is (GaN) 1−x (ZnO) x (Ga:Zn   =   1:2)   >   (GaN) 1−x (ZnO) x (Ga:Zn   =   1:3)   >   ZnO nanofibers   >   (GaN) 1−x (ZnO) x (Ga:Zn   =   1:4)   >   (GaN) 1−x (ZnO) x (Ga:Zn   =   1:1). The photocatalytic mechanism of the (GaN) 1−x (ZnO) x hollow nanofibers was further studied by UV–vis diffuse reflectance spectra. The excellent photocatalytic performance of (GaN) 1−x (ZnO) x hollow nanofibers was attributed to the narrow band gap and high surface area of porous nanofibers with hollow structure.