PNNL

Abstract

In this paper, we present the results of a detailed investigation of the structural, optical and magnetic properties of chemically synthesized pure and Co doped SnO2 powders using x-ray diffraction (XRD), diffuse reflectance spectroscopy, Raman spectroscopy, x-ray photoelectron spectroscopy and magnetometry. For low doping concentrations of Co (= 1%), the SnO2 lattice contracts and a ferromagnetic behavior is developed. Increasing the Co doping concentration to > 1% leads to a rapid expansion of the lattice and significant structural disorder evidenced by changes in the XRD and Raman spectra presumably due to additional interstitial incorporation of Co. This higher Co doping completely destroys the ferromagnetism. The striking similarity between the changes in the lattice parameters and the magnetic properties of Sn1-xCoxO2 indicates a structure-magnetic property relationship.