La(OH)3:Ln3+ (Ln=Sm, Er, Gd, Dy, and Eu) nanorods synthesized by a facile hydrothermal method and their enhanced photocatalytic degradation of Congo red in the aqueous solution

The stable and crystalline phase Ln (Ln=Sm, Er, Gd, Dy, and Eu) doped La(OH)3 (La(OH)3:Ln3+) nanorods were synthesized by a facile hydrothermal method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to examine the microstructure and morphology. The analysis reveals that the obtained compounds are one-dimensional (1D) rod-like nanostructures. The photodegradation of La(OH)3:Ln3+ nanorods was tested by measuring the degradation of azo dye Congo red (CR). The experiments demonstrated that La(OH)3:Ln3+ nanorods degraded CR much faster than undoped La(OH)3 nanorods and the photodegradation efficiency of La(OH)3:Ln3+ nanorods was significantly higher than that of undoped La(OH)3 nanorods.