Person:
Sánchez Benítez, Francisco Javier

Profile Picture
First Name
Francisco Javier
Last Name
Sánchez Benítez
URI
https://hdl.handle.net/20.500.14352/76240
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Física
Area
Química Física
Identifiers
UCM identifierORCIDScopus Author IDWeb of Science ResearcherIDDialnet IDGoogle Scholar ID

Filters

2015 - 20172
Reset filters

Settings

Subject: 546 ×

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Anti-site disorder and physical properties in microwave synthesized RE2Ti2O7 (RE = Gd, Ho) pyrochlores
    (RSC Advances, 2015) Gómez-Pérez, Alejandro; Prado Gonjal, Jesús De La Paz; Muñoz Gil, Daniel; Andrada Chacón, Adrián; Sánchez Benítez, Francisco Javier; Morán Miguélez, Emilio; Azcondo, MaríaTeresa; Amador, Ulises; Schmidt, Rainer
    In this work we report on the microwave assisted synthesis of nano-sized Gd2Ti2O7 (GTO) and Ho2Ti2O7 (HTO) powders from the RE2Ti2O7 pyrochlore family (RE ¼ rare earth). Synchrotron X-ray powder diffraction was used to study RE–Ti cationic anti-site defects with concentrations that decrease in both samples with increasing temperature starting from 1100 C, and the defects disappear at 1400 ºC. SQUID magnetometry measurements revealed that GTO shows a predominantly anti-ferromagnetic structure, whereas HTO exhibits magnetic saturation and a ferromagnetic component at low temperature. Impedance spectroscopy data revealed strongly increased ionic oxygen vacancy conduction in HTO ceramic pellets as compared to GTO, which may be associated with a higher degree of oxygen vacancy disorder. This argument was supported by Raman spectroscopy data.
  • Thumbnail Image
    Item
    Large magnetoelectric coupling near room temperature in synthetic Melanostibite Mn2FeSbO6
    (Angewandte Chemie: International Edition, 2017) Dos Santos García, Antonio Juan; Solana Madruga, Elena; Ritter, Clemens; Sáez Puche, Regino; Andrada-Chacón, Adrián; Sánchez Benítez, Francisco Javier; Mompean, Federico ; Garcia-Hernandez, Mar; Schmidt, Rainer
    Multiferroic materials exhibit two or more ferroic orders and have potential applications as multifunctional materials in the electronics industry. A coupling of ferroelectricity and ferromagnetism is hereby particularly promising. We show that the synthetic melanostibite mineral Mn2FeSbO6 (R-3 space group) with ilmenite-type structure exhibits cation off-centering that results in alternating modulated displacements, thus allowing antiferroelectricity to occur. Massive magnetoelectric coupling (MEC) and magnetocapacitance effect of up to 4000% was detected at a record high temperature of 260 K. The multiferroic behavior is based on the imbalance of cationic displacements caused by a magnetostrictive mechanism, which sets up an unprecedented example to pave the way for the development of highly effective MEC devices operational at or near room temperature.