abstract
Peptide nanotubes based on short dipeptide diphenylalanine (FF) attract a lot of attention due to their unique physical properties ranging from strong piezoelectricity to extraordinary mechanical rigidity. In this work, we present the results of high-resolution Piezoresponse Force Microscopy (PFM) measurements in FF microtubes prepared from the solution. First in-situ temperature measurements show that the effective shear piezoelectric coefficient d(15) (proportional to axial polarization) significantly decreases (to about half of the initial value) under heating up to 100 degrees C. The piezoresponse becomes inhomogeneous over the surface being higher in the center of the tubes. Further, PFM study of a composite consisting of FF microtubes and reduced graphene oxide (rGO) was performed. We show that piezoelectric properties of peptide microtubes are significantly modified and radial (vertical) piezoresponse appears in the presence of rGO as confirmed via PFM analysis. The results are rationalized in terms of molecular approach in which pi - pi molecular interaction between rGO and dipeptide is responsible for the appearance of radial component of polarization in such hybrid structures.
subject category
Materials Science
authors
Ivanov, M; Bak, O; Kopyl, S; Vasilev, S; Zelenovskiy, P; Shur, V; Gruverman, A; Kholkin, A
our authors
Groups
G2 - Photonic, Electronic and Magnetic Materials
G3 - Electrochemical Materials, Interfaces and Coatings
acknowledgements
The reported study was supported by the Portuguese-NSF grant FLAD 299/ 2015 and funded by RFBR, according to the research project No. 16-32- 60188 mol_ a_ dk. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials (POCI-01-0145-FEDER007679, FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/ MEC and, when appropriate, co-financed by FEDER under the PT2020 Partnership Agreement The President of Russian Federation grant for young scientists (MK-2294.2017.2) is also acknowledged.