Light trapping enhancement of inverted polymer solar cells with a nanostructured scattering rear electrode

High performance inverted polymer solar cell is demonstrated by introducing a nanostructured backscattering rear electrode, which is fabricated by embedding silver nanoparticle (NP) arrays into the MoO3 hole extraction layer. As verified by characterizing and simulating the electrical and optical properties, such a nanostructured rear electrode can achieve an improved cell performance by maintaining simultaneously high open-circuit voltage and fill factor values, while providing excellent short-circuit current enhancement through efficient backscattering-induced light trapping. A careful optimization of the nanostructured rear electrode can result in polymer solar cells with an enhanced power conversion efficiency of 7.21%, as compared to 6.26% of the reference cell with a flat electrode. It is noteworthy that the method described here offers a convenient and scalable way for inexpensive and high-performance polymer solar cell designs. (C) 2013 Elsevier B.V. All rights reserved.