Towards plastic electronic sensing devices with TTF-based molecular conductors as active components
- Autores: Victor Lebedev
- Directores de la Tesis: Jaume Veciana i Miró (dir. tes.), Rosa M. Sebastián Pérez (dir. tes.), Elena Laukhina (dir. tes.)
- Lectura: En la Universitat Autònoma de Barcelona ( España ) en 2014
- Idioma: inglés
- Tribunal Calificador de la Tesis: Fernando Palacio Parada (presid.), Mariano Campoy Quiles (secret.), Norberto Masciocchi (voc.)
- Materias:
- Enlaces
- Resumen
The thesis provides an investigation of the all-organic conductive sensing materials for biomedical applications. The methods and techniques used in the thesis are adopted to the subject matter and they are properly justified and applied. It was shown that the elastic, electro-mechanical and electro-transport properties of the conductive layer of the TTF-based molecular conductors, which are developed at the surface of polymeric films, may be controlled by the temperature of the layer formation. Several simple prototypes based on highly strain sensitive bi layer films enabling to perform pressure monitoring with high accuracy in the range of mbar and hundreds bar were developed. Remarkable is the hybrid contact lens sensing device developed with one of such prototypes that fulfill the main requirements to measure the intraocular pressure of humans. This thesis also strongly contributes on the ongoing research of developing smart textiles for their biomedical applications: (1) a protocol of the preparation of conductive fabric, which responds fast and in a reversible manner to extremely small temperature changes, was developed; thanks to this method the polycarbonate/TTF-based molecular semiconductor bi layer films were successfully located on textile as the highly temperature sensing components. (2) The thesis demonstrates that bi layer films capable of controlling RH changes in the range 20-90 % RH can be prepared. These films may be also embedded in textile using the above mentioned method. Such composite textiles can be easily prepared at low cost and they are compatible with printing techniques. The thesis makes a contribution to knowledge that rests on originality of approach in some cases that permits discovering the new facts in the nature of TTF-based organic conductors. 1. The thesis discoveries the relationship between anisotropy of Young¿s modulus of the single crystals of some molecular (BEDT-TTF)-based conductors and the short anion-donor and donor-donor interface contacts existing in their crystals structure. This opens a door to engineering novel organic molecular conductors with the desired anisotropy of mechanical properties. The results of nanoscale mechanical tests presented in the thesis show that there is a very small difference between of Young¿s moduli of BEDT-TTF-based molecular conductors and elastic constants of commonly used commercial polymers. As the similarity of the elastic properties of layered components is one of the key requirements for fabricating robustness electronic layered structures, covering polymeric films with thin layers of (BEDT-TTF)-based conductors has to result in flexible conducting materials, robustness of which is significantly higher than that of polymeric films metalized with conventional metals. 2. This thesis gives the first demonstration of the capability to cover substrates, which are different in composition and geometric form, with flexible all-organic electrical strain sensing layers of molecular conductors. In addition to various potential device applications, such as for humidity sensors and electrical current driven actuators, the sensing layer can also be used to study water diffusion processes. The results presented in the thesis should open the door to novel applications of organic molecular metals in sensing and other related technologies.
