A visual inspection of the Raman spectra

ZnO with a wide band gap (3.3 eV) and large exciton binding URMC-099 (60 meV) is the most studied material because of its wide range of applications in the field of optoelectronics devices [1], [2], [3] and [4]. Although ZnO had been widely researched material for the past decades, the renewed interests are focused on the modifications in various physical properties by rare earth dopants. It has been shown that doping rare earth ions enable ZnO as a multifunctional system. For instance, Ce doping results in the reduction of band gap (red shift) [5] whereas Er doping enhances the band gap (blue shift) of the material [6]. Apart from band gap engineering, Anandan et al. [7] has reported the relatively high photonic efficiencies and improved photocatalytic activity for La doped ZnO samples. Further, the quenching of UV emission band and observation of strong visible emission at ~618 nm has been reported for Eu doped ZnO [8]. Above studies indicate that the desired modifications can be achieved by selecting suitable rare-earth dopants. However, in the context of realization of devices, sieve tube members is important to understand the crystal structure and the optimization of the procedures as well as the extent of dopant up to which it is soluble in the host matrix. There are many reports on the structural and luminescence properties of rare earth doped ZnO [9] and [10] but there is hardly any report available on the effect of phase segregation. Even though, Yttrium does not directly belong to rare earth group, it exhibits the properties similar to rare earth ions. It has been observed that there is an enhancement in defect-induced green–yellow visible emission which in turn is responsible for the enhanced magnetic performances in Y doped ZnO nanorods.