Proceedings of Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP24)
DOI: https://doi.org/10.29363/nanoge.iperop.2024.061
Publication date: 18th October 2023
Bulk-heterojunction organic photovoltaic cells based on π-conjugated polymers have been intensively investigated in the last few decades. A key to improving the power conversion efficiency is to control the polymer order and morphology as well as the molecular orbital energy levels and the absorption range. Therefore, it is imperative to carefully design the π-conjugated polymers to manage their electronic structures, backbone coplanarity and intermolecular interactions. We have been studying a number of π-conjugated polymers by incorporating various fused heteroaromatic rings into the polymer backbone. In this presentation, I will show the design and synthesis of novel π-conjugated polymers based on newly developed heteroaromatics based on thiazole and thiadiazole moieties. In fact, the power conversion efficiencies of ~12% in the cells based on a fullerene acceptor and ~18% in the cells based on a nonfullerene acceptor was achieved using the newly developed polymers. More importantly, significantly efficient charge generation was realized with small voltage loss. I will discuss how the molecular structure affects the polymer properties and polymer order in the thin film and thereby photovoltaic performances.