000060711 001__ 60711 000060711 005__ 20190709135447.0 000060711 0247_ $$2doi$$a10.1038/srep41732 000060711 0248_ $$2sideral$$a98167 000060711 037__ $$aART-2017-98167 000060711 041__ $$aeng 000060711 100__ $$aLeón Félix, L. 000060711 245__ $$aStructural and magnetic properties of core-shell Au/Fe 3 O 4 nanoparticles 000060711 260__ $$c2017 000060711 5060_ $$aAccess copy available to the general public$$fUnrestricted 000060711 5203_ $$aWe present a systematic study of core-shell Au/Fe 3 O 4 nanoparticles produced by thermal decomposition under mild conditions. The morphology and crystal structure of the nanoparticles revealed the presence of Au core of d = (6.9 ± 1.0) nm surrounded by Fe 3 O 4 shell with a thickness of ~3.5 nm, epitaxially grown onto the Au core surface. The Au/Fe 3 O 4 core-shell structure was demonstrated by high angle annular dark field scanning transmission electron microscopy analysis. The magnetite shell grown on top of the Au nanoparticle displayed a thermal blocking state at temperatures below T B = 59 K and a relaxed state well above T B. Remarkably, an exchange bias effect was observed when cooling down the samples below room temperature under an external magnetic field. Moreover, the exchange bias field (H EX) started to appear at T~40 K and its value increased by decreasing the temperature. This effect has been assigned to the interaction of spins located in the magnetically disordered regions (in the inner and outer surface of the Fe 3 O 4 shell) and spins located in the ordered region of the Fe 3 O 4 shell. 000060711 536__ $$9info:eu-repo/grantAgreement/ES/DGA/E26$$9info:eu-repo/grantAgreement/ES/MINECO/MAT2013-42551 000060711 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/ 000060711 590__ $$a4.122$$b2017 000060711 591__ $$aMULTIDISCIPLINARY SCIENCES$$b12 / 64 = 0.188$$c2017$$dQ1$$eT1 000060711 592__ $$a1.533$$b2017 000060711 593__ $$aMultidisciplinary$$c2017$$dQ1 000060711 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion 000060711 700__ $$aCoaquira, J.A.H. 000060711 700__ $$aMartínez, M.A.R. 000060711 700__ $$0(orcid)0000-0003-1558-9279$$aGoya, G.F.$$uUniversidad de Zaragoza 000060711 700__ $$aMantilla, J. 000060711 700__ $$aSousa, M.H. 000060711 700__ $$aValladares, L.D.L.S. 000060711 700__ $$aBarnes, C.H.W. 000060711 700__ $$aMorais, P.C. 000060711 7102_ $$12003$$2395$$aUniversidad de Zaragoza$$bDpto. Física Materia Condensa.$$cÁrea Física Materia Condensada 000060711 773__ $$g7 (2017), [8 pp.]$$pSci. rep.$$tScientific reports$$x2045-2322 000060711 8564_ $$s1196349$$uhttps://zaguan.unizar.es/record/60711/files/texto_completo.pdf$$yVersión publicada 000060711 8564_ $$s117020$$uhttps://zaguan.unizar.es/record/60711/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada 000060711 909CO $$ooai:zaguan.unizar.es:60711$$particulos$$pdriver 000060711 951__ $$a2019-07-09-11:38:43 000060711 980__ $$aARTICLE