62114 20190709135442.0 doi 10.1039/c7ra00782e sideral 101164 ART-2017-101164 eng Díaz, C. Synthesis and magnetic properties of nanostructured metallic Co, Mn and Ni oxide materials obtained from solid-state metal-macromolecular complex precursors 2017 Access copy available to the general public Unrestricted The simple reaction of chitosan with metallic salts yields (chitosan) (MLn)x, MLn = MnCl2, CoCl2, NiCl2, macromolecular complexes which, after a thermal treatment at 800 °C under air, give nanostructured Mn2O3, Co3O4 and NiO. The polymer acts as a template in the solid state, which is eliminated after the combustion process. At an intermediate stage, a layered graphitic carbon matrix was observed by HRTEM over the grown metal oxides. A mechanism for the growth of nanostructured oxides is discussed, including Raman studies. The nanostructured Mn2O3, Co3O4 and NiO particles grow over graphite layers and the solid-state role of chitosan is crucial for the formation of this graphite substrate. An antiferromagnetic transition was observed in Co3O4 nanoparticles, with TN = 38 K, whereas NiO nanoparticles behave as a superparamagnetic material with a blocking temperature above 300 K. info:eu-repo/semantics/openAccess by-nc http://creativecommons.org/licenses/by-nc/3.0/es/ 2.936 2017 CHEMISTRY, MULTIDISCIPLINARY 71 / 171 = 0.415 2017 Q2 T2 0.863 2017 Chemistry (miscellaneous) 2017 Q1 Chemical Engineering (miscellaneous) 2017 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Valenzuela, M.L. (orcid)0000-0002-7819-8956 Laguna-Bercero, M.A. Universidad de Zaragoza (orcid)0000-0001-8751-0983 Orera, A. Universidad de Zaragoza Bobadilla, D. Abarca, S. Peña, O. 5001 065 Universidad de Zaragoza Dpto. Ciencia Tecnol.Mater.Fl. Área Cienc.Mater. Ingen.Metal. 2003 395 Universidad de Zaragoza Dpto. Física Materia Condensa. Área Física Materia Condensada 7, 44 (2017), 27729-27736 RSC ADVANCES RSC Advances 2046-2069 1955628 http://zaguan.unizar.es/record/62114/files/texto_completo.pdf Versión publicada 115147 http://zaguan.unizar.es/record/62114/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:62114 articulos driver 2019-07-09-11:36:42 ARTICLE