Correlation Between Structural and Optical Properties of Composite Polymer/Fullerene Films for Organic Solar Cells

作者：Tobias Erb, Uladzimir Zhokhavets, G. Gobsch, Sofiya Raleva, Bernd Stühn, Pavel Schilinsky, Christoph Waldauf, Christoph J. Brabec · 发表于：Advanced Functional Materials · 年份：2005 · DOI：10.1002/adfm.200400521 · 被引用次数：831 · 研究领域：Organic Electronics and Photovoltaics、Fullerene Chemistry and Applications、Nonlinear Optical Materials Studies

Abstract We investigate thin poly(3‐hexylthiophene‐2,5‐diyl)/[6,6]‐phenyl C61 butyric acid methyl ester (P3HT/PCBM) films, which are widely used as active layers in plastic solar cells. Their structural properties are studied by grazing‐incidence X‐ray diffraction (XRD). The size and the orientation of crystalline P3HT nanodomains within the films are determined. PCBM crystallites are not detected in thin films by XRD. Upon annealing, the P3HT crystallinity increases, leading to an increase in the optical absorption and spectral photocurrent in the low‐photon‐energy region. As a consequence, the efficiency of P3HT/PCBM solar cells is significantly increased. A direct relation between efficiency and P3HT crystallinity is demonstrated.