ESR spectroscopy for monitoring the photochemical and thermal degradation of conjugated polymers used as electron donor materials in organic bulk heterojunction solar cellsElectronic supplementary information (ESI) available: A detailed description of the experimental procedure; the ESR spectra of PBDTTT-CF; the thermal degradation profiles revealed for conjugated polymers; and the numerical data for the degradation rates of the analyzed conjugated polymers. See DOI: 10.1039/c4cc08146c

It was shown that ESR spectroscopy is a very useful technique for monitoring the photochemical and thermal degradation of conjugated polymers commonly used in organic solar cells. The relative stability of materials can be quantified by comparing the rates of trap accumulation (d C R /d t ) estimated from their ESR profiles. ESR spectroscopy was applied for monitoring the degradation of conjugated polymers used in organic solar cells and comparing their stability.