Cyr, Mélanie2026-05-152026-05-152026-05-15http://hdl.handle.net/10393/51661https://doi.org/10.20381/ruor-31959Organic semiconducting (OSC) materials are now more than ever being exploited in modern technology for the development of next-generation organic electronic devices. These types of materials hold many advantages over their inorganic counterparts such as their mechanical flexibility, solution processibility, lighter density and strong light-matter interactions, to name a few. Nevertheless, their most attractive feature remains their ease of functionalization to adjust and optimize their optical and electronic properties. The slightest change in molecular structure can have a significant impact on the materials' ability to interact with analytes, absorb light and transport charges. This has led OSCs to be exploited in a wide array of fields including optoelectronics, sensors and actuators, energy storage, printed electronics, biomedical applications and more. This thesis looks to developing new donor-acceptor (D-A) small molecules and porphyrinoid macrocycles and evaluate their potential as n-type and p-type OSCs in organic thin-film transistors (OTFTs) as well as their potential in chemical sensing. I synthesized and characterized each novel material at the molecular level and in the solid state when processed into thin-films. The chemical derivatizations allowed to adjust the frontier molecular orbitals (FMOs) and molecular bandgap adopted by each material. I also studied their semiconducting potential in different OTFT device architectures as well as explored different device fabrication conditions to optimize their semiconducting abilities. In the latter work of this thesis, I also explored electropolymerization of silicon phthalocyanine materials to create sensing films onto quartz microbalance (QMB) sensors for mass-based detection and interdigitated electrode (IDE) sensors for electronic-based detection of various gases and volatile organic compounds (VOCs). Overall, this thesis demonstrates the design and functionalization of OSC materials and portrays the importance of structure-property relationships adopted by these materials as they are processed into thin-films for specific organic electronic applications.enAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/Thesis