Fabrication and performance of organic thin film solar cells using a painting method

Abstract

As organic thin film solar cells fabricated by the active layer of organic materials are economical, lightweight, and flexible, as well as generating no CO 2 and being easy to fabricate, they have attracted significant attention as green energy sources from a past decade to date. Therefore, their power conversion efficiency (PCE) has been investigated and studied worldwide. In organic thin-film solar cells, the effect of the performance depends not only on the adopted active material but also relates to the molecular orientation on the electrode. Using a mixed solution of Poly(3-hexylthiophene) and PCBM, both of which were dissolved in a solvent, the organic thin films were fabricated using the paint and spray methods, while the morphology of the thin film was evaluated by an AFM image, UV/vis spectra, and so forth. Based on these data, an organic thin-film solar cell using both solution methods for the active layer was fabricated, and the performance evaluated and examined. For organic thin film solar cells fabricated using a spin-coating method, the open-circuit voltage (Voc) is 0.41V, the short circuit current density (Jsc) is 2.07mA/cm 2 , and the fill factor is 0.34, while the efficiency η of PCE become 0.29%. In the spray method, the short circuit current (Isc) is 2.5 mA/cm 2 , the open circuit voltage (Voc) is 0.45 V, the fill factor (FF) is 0.28, and the power conversion factor (PCE) 0.35%. The area of organic solar cells fabricated by spin coating and spray methods is 1 cm 2 respectively. The organic solar cells are not thermally treated, and hence have high respective power conversion efficiencies.