The areas which have not undergone agglomeration as mentioned previously are having more oxygen vacancies (Fig 3 ) The ratio of atomic % of Ce and O is 2.1 for agglomerated regions showing the formation of CeO2 with negligible vacancies. The ratio changes to 1.66 for regions where agglomeration is less and the particles have maintained their nanometric dimensions, which again matches with Ce-O-Ce bond formation The change in saturation magnetization before and after UV exposure is about 0.018 emu g -1 . The emission peaks in the PL spectra in the blue region are due to oxygen vacancies for an excitation wavelength in the UV region. The absorption band edge was also obtained in the UV region. The photocatalytic activity of Ce-ZnO has also been found to be most effective in the UV region. However, what is promising to see from all these characterizations performed is that defect generation takes place in the visible region as well evident from the emission peaks at wavelengths greater than 550 nm which may cause room temperature Ferromagnetism in the visible region as well. Ceria is also used in solid oxide fuel cells (SOFC) which are also affected by charge transfer related to oxygen vacancies.