resumo
Magnetic behavior of Co-II(n)Al-III layered double hydroxides (LDHs) (n = Co/Al = 2 and 3) intercalated with nitrate was studied as a function of temperature. Both LDH compounds are paramagnetic above about 8K. A rapid increase of their magnetic moments occurs below this temperature until the moments reach the maximum values at T-max of 4.0 K and 3.2 K for Co(2)Al-NO3 and Co(3)Al-NO3, respectively. Below T-max, the zero-field-cooled and the field-cooled static magnetization curves are strongly different. Along with this low-temperature phenomena, Co(2)Al-NO3 and Co(3)Al-NO3 demonstrate anomalous behavior of their temperature dependence magnetic susceptibility in a higher-temperature range: between 75 and 175 K, both the paramagnetic Curie temperature and the effective magnetic moment change in a non-monotonous way. Possible structural reasons of the observed magnetic behavior of the Co-II(n)Al-III LDHs are discussed. Published by AIP Publishing.
palavras-chave
X-RAY-DIFFRACTION; INTERCALATION; AL
categoria
Physics
autores
Vieira, DEL; Salak, AN; Fedorchenko, AV; Pashkevich, YG; Fertman, EL; Desnenko, VA; Babkin, RY; Cizmar, E; Feher, A; Lopes, AB; Ferreira, MGS
nossos autores
Andrei Salak
Investigador Principal
Augusto Luís Barros Lopes
Professor Auxiliar
Daniel Eduardo Loureiro Vieira
Estudante de doutoramento
Mário Guerreiro Silva Ferreira
Professor(a) Jubilado(a)Grupos
G2 - Materiais Fotónicos, Eletrónicos e Magnéticos
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
agradecimentos
The work was supported by project TUMOCS. This project has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant Agreement No. 645660. The financial supports of the Slovak Research and Development Agency under Contract Nos. APVV-14-0073 and APVV-0132-11, and the supports of P2020 COMPETE and FCT-Portugal through project POCI-01-0145-FEDER-016686-PTDC/CTM-NAN/2418/2014 (NANOCONCOR) are gratefully acknowledged as well.