A Ferroelectric Aminophosphonium Cyanoferrate with a Large Electrostrictive Coefficient as a Piezoelectric
Thangavel Vijayakanth1,2, Supriya Sahoo1, Premkumar Kothavade3
1Department of Chemistry and Centre for Energy Science, Indian Institute of Science Education and Research, Pune, Dr. Homi Bhabha Road, Pune, 411008, India.
Abstract:
Hybrid materials possessing piezo- and ferroelectric properties emerge as excellent alternatives to conventional piezoceramics due to their merits of facile synthesis, lightweight nature, ease of fabrication and mechanical flexibility. Inspired by the structural stability of aminophosphonium compounds, here we report the first A3 BX6 type cyanometallate [Ph2 (i PrNH)2 P]3 [Fe(CN)6 ] (1), which shows a ferroelectric saturation polarization (Ps ) of 3.71 μC cm-2 . Compound 1 exhibits a high electrostrictive coefficient (Q33 ) of 0.73 m4 C-2 , far exceeding those of piezoceramics (0.034-0.096 m4 C-2 ). Piezoresponse force microscopy (PFM) analysis demonstrates the polarization switching and domain structure of 1 further confirming its ferroelectric nature. Furthermore, thermoplastic polyurethane (TPU) polymer composite films of 1 were prepared and employed as piezoelectric nanogenerators. Notably, the 15 wt % 1-TPU device gave a maximum output voltage of 13.57 V and a power density of 6.03 μW cm-2 .
