A review of polymer multijunction solar cells

Polymer solar cells are one of the most promising prospects for widespread renewable energy due to their low cost, light weight, and mechanical flexibility. However, to date, low efficiencies (7.9%) of these devices inhibit their application. New materials and device designs are needed to increase the efficiency and make this technology available for large-scale applications. A polymer multijunction solar cell made of two or more subcells in series, parallel, or other special connections offers a potential solution to the losses in the current polymer single-junction solar cells. In this article, the recent developments in polymer multijunction photovoltaic materials, cell structures, and device modelling are reviewed. In addition, the current challenges that need to be addressed to achieve siginificantly higher efficiency are discussed.