Study of the piezoelectricity in iron-doped collagen films

Abstract

In this paper a study was carried out of collagen membranes prepared with iron as an impurity. In this study the function of the iron in the collagen structure was examined with the aim of increasing the value of the piezoelectric strain tensor element d ₁₄. We prepared different samples with different iron doping levels. Doped samples by immersion in solutions of FeCl₂ (0.1 M and 0.2 M), FeCl₃ (0.1 M) and FeNH₄SO₄ (0.1 M) and iron doped directly in solution with Fe₂O₃ at 5% and 15% were examined. Mössbauer spectroscopy, the piezoelectric strain tensor element d ₁₄ the elastic constant s ₅₅, and the dielectric function ɛ₁₁ of the samples were examined. The loss factor Q ⁻¹ of the samples was also measured using the admittance resonance method. The role played by the iron in the different situations and the consequences for the transport properties are discussed.