Tuning red emission and photocatalytic properties of highly active ZnO nanosheets by Eu addition

Abstract

Eu-doped ZnO nanosheets were synthesized via a facile and surfactant-free chemical solution deposition method. The detailed characterizations revealed that the as-synthesized samples were well-crystalline which assembled by nanosheets with 25 nm thickness. The Eu ions were successfully doped into the ZnO nanosheets, and the red emissions of Eu3+ ions attributed to the energy of 5D0→7F0, 5D0→7F1 and 5D0→7F2 4f–4f intrashell transitions were observed in PL spectra. The appropriate Eu doping would increase the separation efficiency of electron-hole pairs and promote the formation of the superoxide ions during the photolysis process, which eventually improved the photodegradation of Rhodamine B under UV light irradiation. And the photocatalytic degradation of RhB was also analyzed by a pseudo first order rate. A possible explanation for the modification of bandgap was given based on the modified effect of Eu3+ ions on the electronic structure of ZnO nanosheets, which mainly due to two mechanisms of Burstein-Moss effect and electron-ion/electron scattering.