[3PS-021]
Structural Origins of Polarity Switching in Heavily Doped Conjugated Polymers
발표자옥은솔 (포항공과대학교)
연구책임자조길원 (포항공과대학교)
Abstract
Recent progress in organic semiconductors has revealed the promise of conjugated polymers for flexible electronics, while stable n-type behavior remains challenging. Here, we investigate the chemical and structural origins of polarity switching in a heavily doped conjugated polymer. Using AuCl₃-doped IDTBT as a model system, we show that high dopant concentrations induce chemical oxidation and covalent chlorination of the polymer backbone, accompanied by significant thin-film structural reorganization. X-ray photoelectron spectroscopy directly confirms dopant oxidation-state changes and backbone modification, establishing a clear link between doping chemistry, structural transformation, and polarity switching. Based on this mechanism, a p–n homojunction organic diode is fabricated from a single polymer by controlling dopant concentration, achieving rectification ratios of 10⁴–10⁵.