Y2O3 nanofibers and nanobelts were fabricated by calcination of the respective electrospun PVP/Y(NO3)(3) composite nanofibers and nanobelts. For the first time, Y2O2CN2 nanofibers and nanobelts were successfully prepared via cyanamidation of the respective Y2O3 nanofibers and nanobelts employing NH3 gas and using graphite boat as container at 950 degrees C. X-ray power diffraction (XRD) analysis reveals that Y2O2CN2 nanofibers and nanobelts are pure trigonal phase with the space group of P (3) over bar m1. Scanning electron microscope (SEM) observation indicates that the diameter of Y2O2CN2 nanofibers is 167.59 +/- 31.19 nm, and the thickness and width of Y2O2CN2 nanobelts are respectively 154 nm and 2.02 +/- 0.84 mm under the 95% confidence level. Fourier transform infrared spectroscopy (FTIR) analysis manifests that the trigonal Y2O2CN2 nanofibers and nanobelts contain CN22- ions. Brunauer-Emmett-Teller surface area (BET) measurement shows the surface areas of the Y2O2CN2 nanofibers and nanobelts are 19.13 m(2) g(-1) and 15.92 m(2) g(-1), respectively. Y2O2CN2 nanostructures with different morphology exhibit high-efficiency photocatalytic capacity in photodegradation of rhodamine B (RhB) under the ultraviolet light irradiation, and the nanofibers have higher photocatalytic ability than nanobelts under the same experimental conditions. Furthermore, the nanofibers and nanobelts retain excellent photocatalytic stability after reused for four times. The photocatalytic mechanism and formation process of Y2O2CN2 nanofibers and nanobelts are also provided.