La2O3 nanofibers and nanobelts were fabricated by calcination of the respective electrospun PVP/[La(NO3)(3)] composite nanofibers and nanobelts. For the first time, La2O2CN2 nanofibers and nanobelts were successfully prepared via cyanamidation of La2O3 respective nanostructures employing NH3 gas and graphite at high temperature. X-ray powder diffraction (XRD) analysis reveals that La2O2CN2 nanostructures are tetragonal in structure with space group of I4/mmm. Scanning electron microscope (SEM) analysis indicates that the thickness and the width of La2O2CN2 nanobelts are respectively 180 am and 2.56 +/- 0.68 mu m, and the diameter of La2O2CN2 nanofibers is 248.10 +/- 40.98 nm under the 95% confidence level. Transmission electron microscope (TEM) observation shows that La2O2CN2 nanofibers and nanobelts are all composed of nanoparticles. La2O2CN2 nanostructures with different morphology exhibit excellent photocatalytic activity in photodegradation of rhodamine B (RhB) under ultraviolet light irradiation, and the nanofibers have higher photocatalytic ability than nanobelts under the same experimental conditions. The possible formation mechanisms of La2O2CN2 nanofibers and nanobelts were also proposed. (C) 2014 Elsevier B.V. All rights reserved.