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09:34
Synthesis and Characterization of Fe-doped Aluminosilicate Nanotubes with Enhanced Electron Conductive Properties
Published on: November 15, 2016
New ferroelectrics based on divalent metal ion alum.
Wen Zhang1, Li-Zhuang Chen, Ren-Gen Xiong
1Ordered Matter Science Research Center, Southeast University, Nanjing 211189, PR China.
Journal of the American Chemical Society
|August 19, 2009
Summary
Two new alum-type complexes, copper(II) bis(selenate) and its deuterated version, exhibit ferroelectric properties. These compounds undergo a phase transition due to cation and anion ordering.
Area of Science:
- Materials Science
- Solid State Chemistry
- Crystallography
Background:
- Alum-type complexes are a well-studied class of crystalline solids.
- Ferroelectricity in alum analogues has primarily been observed in trivalent metal systems.
- The exploration of divalent metal-based ferroelectrics is an active area of research.
Purpose of the Study:
- To synthesize and characterize new alum-type complexes containing the selenate anion.
- To investigate the ferroelectric properties of these novel compounds.
- To determine the mechanism of the paraelectric-ferroelectric phase transition.
Main Methods:
- Single-crystal X-ray diffraction to determine crystal structure.
- Differential scanning calorimetry (DSC) for phase transition analysis.
- Dielectric measurements to confirm ferroelectric behavior.
Main Results:
- Two new alum-type complexes, (H(2)dbco)Cu(H(2)O)(6)(SeO(4))(2) and its deuterated analogue, were successfully synthesized.
- Both compounds exhibit ferroelectricity with a phase transition occurring around -140 to -138 °C.
- The phase transition is attributed to order-disorder phenomena involving the 1,4-diazoniabicyclo[2.2.2]octane cation and the selenate anion.
Conclusions:
- These are the first reported ferroelectrics based on divalent metal anion alum analogues.
- The findings expand the scope of known ferroelectric materials and provide insights into structure-property relationships in alum-type compounds.
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