Investigation of Cation and Cation Vacancy Distributions in the Zinc Substituted Maghemite, Prepared by One Pot Room Temperature Co-precipitation Method

The cation and cation vacancy distributions in Zn 2+ substituted maghemite (γ-Fe 2 (1-x/3) Zn x O 3 , x = 0.0, 0.1, 0.2, 0.3 and 0.4) nanoparticles, which were synthesized directly via one pot room temperature co-precipitation method, were obtained by positron annihilation lifetime spectroscopy, coincidence Doppler broadening spectroscopy, and Rietveld refinement of XRD patterns. The analyses show that the substitution of small amounts of zinc ions for iron ones in maghemite (x ≤ 0.1) leads to an increase in the number of cation vacancies, while more substitutions cause to a decrease in cation vacancies. For the samples with x = 0.0 and 0.1, more of vacancies are placed at B sites, whereas for others they are placed at the A ones.