Temperature-driven phase transformation in self-assembled diphenylalanine peptide nanotubes
Por:
Heredia A., Bdikin I., Kopyl S., Mishina E., Semin S., Sigov A., German K., Bystrov V., Gracio J., Kholkin A.L.
Publicada:
1 ene 2010
Resumen:
Diphenylalanine (FF) peptide nanotubes (PNTs) represent a unique class of self-assembled functional biomaterials owing to a wide range of useful properties including nanostructural variability, mechanical rigidity and chemical stability. In addition, strong piezoelectric activity has recently been observed paving the way to their use as nanoscale sensors and actuators. In this work, we fabricated both horizontal and vertical FF PNTs and examined their optical second harmonic generation and local piezoresponse as a function of temperature. The measurements show a gradual decrease in polarization with increasing temperature accompanied by an irreversible phase transition into another crystalline phase at about 140-150 °C. The results are corroborated by the molecular dynamic simulations predicting an order-disorder phase transition into a centrosymmetric (possibly, orthorhombic) phase with antiparallel polarization orientation in neighbouring FF rings. Partial piezoresponse hysteresis indicates incomplete polarization switching due to the high coercive field in FF PNTs. © 2010 IOP Publishing Ltd.
Filiaciones:
Heredia A.:
Department of Ceramics and Glass Engineering and CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
Bdikin I.:
Centre for Mechanical Technology and Automation (TEMA), University of Aveiro, 3810-193 Aveiro, Portugal
Kopyl S.:
Centre for Mechanical Technology and Automation (TEMA), University of Aveiro, 3810-193 Aveiro, Portugal
Mishina E.:
Moscow State Institute of Radioengineering, Electronics and Automation, 119454 Moscow, Russian Federation
Semin S.:
Moscow State Institute of Radioengineering, Electronics and Automation, 119454 Moscow, Russian Federation
Sigov A.:
Moscow State Institute of Radioengineering, Electronics and Automation, 119454 Moscow, Russian Federation
German K.:
Institute of Applied Physics, Kishinev, MD-2028, Moldova
Bystrov V.:
Department of Ceramics and Glass Engineering and CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
Institute of Mathematical Problems of Biology, Puschino, Moscow District, Russian Federation
Gracio J.:
Centre for Mechanical Technology and Automation (TEMA), University of Aveiro, 3810-193 Aveiro, Portugal
Kholkin A.L.:
Department of Ceramics and Glass Engineering and CICECO, University of Aveiro, 3810-193 Aveiro, Portugal
All Open Access; Green
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