Artículos de revistas
EPR of Mn as densifying agent in SnO2 powders
Fecha
1999-08-01Registro en:
Solid State Sciences, v. 1, n. 6, p. 331-337, 1999.
1293-2558
10.1016/S1293-2558(00)80087-4
WOS:000084083800002
2-s2.0-0012872012
Autor
Universidade Estadual Paulista (Unesp)
Universidade de São Paulo (USP)
Institución
Resumen
Electron Paramagnetic Resonance (EPR) spectra have been obtained at room temperature and at X-band in powders of SnO2 doped with Mn from 0.3 to 10% and submitted to heat treatment from 500 to 900 °C. Mn ions are probably located at particle surfaces as Mn2+, evidenced by its single EPR line which narrows by the exchange interaction effect due to particle growth observed by the BET technique. In samples doped above 1% formation Of Mn3O4 is detected on particle surfaces and a small quantity of Mn is thermally diffused into the bulk as Mn4+. Powders compacted and sintered at 1300 °C confirmed that Mn2+ ions remain at grain boundaries acting as densifying agent.