4. Conclusions

Magnetoelectric nanocomposites were successfully produced using piezoelectric phase PVDF-TrFE and magnetostrictive phase CoFe2O4 nanoparticles by a simple solvent casting method. The resultant multiferroic films exhibit saturated hard magnetic properties and a magnetoelectric coefficient dependent on the loading of the magnetostrictive phase. The presence of low content of nanoparticles in the composite significantly improves the polarization and piezoelectric responses of the copolymer matrix, demonstrating that low filler content CoFe2O4/PVDF-TrFE nanocomposites are promising candidates for room temperature piezoelectric and ferroelectric applications. The magnetoelectric response

is among the highest reported in particulated polymer nanocomposites, this work provides a promising way to produce flexible magnetoelectric materials to be applied in smart devices.

Acknowledgments

The authors thank Jaime Silva and Jieci Wang for their help with the theoretical modelling. This work was supported by FEDER ‘Programa Operacional Factores de Competitividade– COMPETE’ (NANO/NMed-SD/0156/2007) and Fundac¸ao˜ para a Cienciaˆ e a Tecnologia FCT (PTDC/CTM/69316/2006). PM acknowledges support from FCT (SFRH/BD/45265/2008). Technical and human support for magnetic measurements provided by SGIker (UPV/EHU, MICINN, GV/EJ, ESF) is gratefully acknowledged. J M Barandiaran and J Gutierrez acknowledge the financial support from the Basque Government Industry Department under Project Actimat, (ETORTEK-IE10-272). The authors also acknowledge the support of the COST Action MP1003, 2010: The ‘European Scientific Network for Artificial Muscles’ (ESNAM).

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