Influence of N-doping on photocatalytic activity of ZnO nanoparticles under visible light irradiation

Abstract

N-doped ZnO nano-particles are synthesized by preparing pristine ZnO using sol–gel method and later nitrogenating it by passing nitrogen gas. XRD analysis of sample showed the formation of pure wurtzite phase of ZnO. Optical studies showed a red-shift in the absorbance spectrum after N doping. Raman analysis also supports the formation of defect states in ZnO. The photocatalytic activity of ZnO and N-doped ZnO is evaluated by evaluating rate of degradation of methylene blue and phenol at room temperature under visible light. The N-doped ZnO shows higher photocatalytic activity compared to pristine ZnO and Degussa P-25. The enhancement in the activity is attributed to nitrogen doping induced elevated absorption, high oxygen vacancies and small particle size of the ZnO nanoparticles.