Stoichiometric Control Over Ferroic Behavior in Iron Doped Barium Titanate Nanocrystals


Graduate student Long Yang, in collaboration with the group of Prof. Stephen O’Brien at The City College of New York recently had a paper accepted in the journal Chemistry of Materials that describes the multiferroic behavior in the iron doped barium titanate nanocrystals. (

Materials that exhibit both ferroelectric and ferromagnetic
(ferroic) properties and their application in future storage
devices have attracted people’s great attentions. A device in which
the magnetization is controlled by an electric field, preferably at
low voltages, at room temperature and with ultrafast switching, is
a prime goal. But preparing single phase nanocrystalline
multiferroics is a synthetic challenge.

Prof. Stephen O’Brien’s group at Department of Chemistry at the
City College of New York, developed the novel synthesis called gel
collection, while our group led the structural characterization,
together with the researcher Dr. Zheng Gai from Oak Ridge National
Laboratory who performed magnetic characterizations. This study,
published in Chemistry of Materials, gives solid evidence of
non-centrosymmetric structure, lattice expansion, and confirmation
of successful iron doping using this novel synthesis. The sub 10 nm
uniformly dispersed nanocrystalline samples were shown to be
multiferroic, exhibiting both ferroelectricity and

The work in the Billinge group was funded by the National Science
Foundation (NSF) MRSEC program through Columbia in the Center for
Precision Assembly of Superstratic and Superatomic Solids, and in
the O’Brien’s group by NSF. The PDF experiments were carried out at
the XPD beamline at the NSLS-II at Brookhaven National Laboratory,
and the magnetic characterization was conducted at the Center for
Nanophase Materials Science at Oak Ridge National Laboratory.