Design and Fabrication of Photonic Structured Organic Solar Cells by Electrospraying

Abstract

Photonic architectures in optoelectronic devices are comprised of uniform periodic structural arrangement which aids in improved interaction with light. The processing of such photonic arrays generally involves several steps of fabrication. This work proposes single-step fabrication of an equal submicron size porous photonic structure array through electrospraying. This distinctive approach involves a continuous supply of material With simultaneous removal of solvent for fabricating large area samples, compared to other processing techniques. The process optimization is carried out to regulate the pore diameter and spacing. Morphological studies showed the continuity of porous arrays extending to large areas of the order of millimeters. Optical investigations demonstrated that this uniform periodic topography assisted in improved light scattering and a consequent enhancement of light absorption. Further, the incorporation of this array structure in the active layer of organic photovoltaic devices is evaluated through both experiments and modeling. Modeling and simulations suggest that the optimized range of 200-500 mm pore size aids in higher current density. Experiments reveal an improvement of 18% in the photocurrent density at short circuit in the periodic array architecture compared to the planar reference. Therefore, in this study, a facile single-step novel, method of obtaining photonic array structures with unproved device performances is demonstrated.