Double junction polymer solar cells

The growing need for low-cost alternative energy motivates research in polymer solar cells. To reduce the cost per watt of energy, polymer solar cells with high power conversion efficiencies are necessary. Tandem polymer solar cells can achieve significantly higher efficiencies; however there are issues associated with polymers' complementary absorption spectra, architectural designs, fabrication approaches and interfacial material selections or engineering. In this article, we review device structures: both regular and inverted architectures, efficiency estimation of double junction polymer solar cells, and the most recent progress in circumventing the limitations of tandem polymer solar cells. This article will provide the readers with insightful knowledge into developing tandem polymer solar cells with efficiencies towards 15%.