On Friday, December 14, 2018, Zeinab EL MOUSSAWI, a doctoral student in Materials Science, Mechanical Engineering, Civil Engineering, and Electrochemistry at the Laboratory of Electrochemistry and Physicochemistry of Materials and Interfaces (LEPMI), will defend her thesis titled“Nano-architectured composite materials based on carbon nanotubes for photovoltaic applications.”
The defense will take place at 10 a.m. in Lecture Hall 1 at the IUT Chambéry, on the Bourget-du-Lac campus.
Thesis summary
The use of carbon nanotubes (CNTs) in photovoltaic (PV) cells is limited to their application as electrodes or as dopants in the active layer due to their extremely high conductivity, which causes short circuits within the cell. As part of this thesis, we proposed and validated a new concept involving the development of SWNTs as alternative active acceptor materials to PCBM (a fullerene derivative) for organic photovoltaics. We developed a chemical synthesis route based on the controlled functionalization of SWNTs and the quantification of their degree of functionalization. This new concept will enable the development of “custom-made” SWNTs with tunable conductivities and optical and electrochemical properties that are suitable for integration into heterojunction photovoltaic devices with commercial pi-conjugated polymer donors. Characterization of the final properties of the synthesized SWNTs has shown that conductivity, UV-visible absorption, and electrochemical properties evolve gradually in two distinct ways depending on the degree of functionalization. Furthermore, the controlled functionalization of SWNTs induces a dispersing effect that facilitates their integration into PV devices using existing solvent-based processing technologies such as inkjet printing or roll-to-roll thin-film fabrication. This proof of concept was validated through testing in PV cells using a standard commercial P3HT polymer and a synthesized polymer with a narrow optical bandgap.