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Supporting Information

Microwave-Induced Plasma Assisted Synthesis of Ternary Titanate and Niobate Phases

David J. Brooks, Rik Brydson and Richard E. Douthwaite

Department of Chemistry, University of York, York YO10 5DD, UK. Fax: +44 (0)1904

432516; Tel: +44 (0)1904 432516; E-mail: red4@york.ac.uk

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Materials Characterization

X-ray diffraction: Samples were prepared by grinding powders in a mortar and pestle and

fixed into a sample holder with a glass slide. Except for Ba2TiO4 phases, patterns were

collected on Philips 1800 Diffractometer (PH 03) with CuKα radiation (λ = 1.54 Å) from 20

to 80o in reflection mode at a scanning rate of 2o per minute with a step size of 0.04o.

Ba2TiO4 phases were collected at a scanning rate of 0.5o per minute with a step size of 0.04o.

X-ray patterns were compared to reference patterns available from the JCPDS.

Electron Microscopy: Particle size and morphology were characterized in a field emission

SEM (Sirion 200). Samples were mounted on conductive carbon tapes that were attached to

the surface of SEM brass stubs. All samples were then coated with gold using a Polaron

Equipment Ltd SEM Coating Unit E5000 (30mA, 0.2-0.1 Torr), to minimise charging

effects. Further microstructural and microchemical analysis using transmission electron

microscopy (TEM) was carried out using a FEI CM200 field emission TEM operated at 200

kV and fitted with an ultra thin window Oxford Instruments energy dispersive X-ray (EDX)

detector and Gatan GIF200 electron energy loss (EELS) imaging filter. Samples of the

powder were dispersed in methanol, ground and pipetted onto a holey carbon coated copper

TEM grid. EELS spectra were recorded from areas a few hundred nanometres in diameter

with the microscope operating in diffraction mode with a collection semi-angle of 6 mrads

and were quantified using the titanium L2,3-, oxygen K- and barium M 4,5-edges over an

integration window of 50 eV using hydrogenic cross-sections with a white line correction.

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Powder X-ray Patterns

Fig.1 Powder X-ray diffraction pattern of plasma prepared LiNbO3 and JCPDS-78-0250 data file.

Fig.2 Powder X-ray diffraction pattern of plasma prepared NaNbO3 and JCPDS-33-1270 data file.

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Fig.3 Powder X-ray diffraction pattern of plasma prepared KNbO3 and JCPDS-32-0822 data file.

20 30 40 50 60 70 80�2Theta

0

100

200

300

400

500

600counts

20 30 40 50 60 70 80�2Theta

0

100

200

300

400

500

600counts

Fig.4 Powder X-ray diffraction pattern of plasma prepared CaTiO3 and JCPDS-86-1393 data file.

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Fig.5 Powder X-ray diffraction pattern of plasma prepared BaTiO3 and JCPDS-75-1606 data file.

0

100

200

300

400

500

600

700

800

20 30 40 50 60 70 80

counts

2 Theta

Fig.6 Powder X-ray diffraction pattern of plasma prepared monoclinic Ba2TiO4 from BaCO3 and JCPDS-35-0813 data file.

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counts

0

100

200

300

400

500

600

700

800

20 30 40 50 60 70 802 theta

Fig.7 Powder X-ray diffraction pattern of plasma prepared orthorhombic Ba2TiO4 from BaO and JCPDS-75-0677 data file.

Fig.8 Powder X-ray diffraction pattern of plasma prepared PbTiO3 and JCPDS-75-0438 data file.

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Fig.9 Powder X-ray diffraction pattern of O2 plasma promoted reaction between BaCO3 and TiO2 after 5 mins(centre) compared to hexagonal BaTiO3 JCPDS-34-0129 (upper) and tetragonal BaTiO3 JCPDS-75-1169(lower) data files.

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Scanning Electron Microscopy

LiNbO3 Plasma LiNbO3 Thermal

NaNbO3 Plasma NaNbO3 Thermal

KNbO3 Plasma KNbO3 Thermal

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BaTiO3 Plasma BaTiO3 Thermal

monoclinic Ba2TiO4 Plasma monoclinic Ba2TiO4 Thermal

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orthorhombic Ba2TiO4 Plasma orthorhombic Ba2TiO4 Thermal

PbTiO3 Plasma PbTiO3 Thermal

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Single Crystal pattern of orthorhombic Ba2TiO4 viewed down [-201]

030

132

012