Low temperature efficient interconnecting layer for tandem polymer solar cells

Abstract

Tandem solar cells are found to be promising in organic photovoltaic research because they can double open-circuit voltage (Voc) and utilize photon energy efficiently, as compared to single junction solar cells. In a typical tandem polymer solar cell, two single subcells are staked and connected by an interconnecting layer, which is a prerequisite to achieving high photo-electron conversion efficiency. In this work, a low temperature solution processed and chemically stable PEDOT:PSS/AZO/PEIE interconnecting layer is reported. Tandem polymer solar cells based on this efficient layer can realize a high Voc, which can sum the Voc׳s of subcells. Furthermore, the operation mechanism of the interconnecting layer is discussed to help better understand the electron recombination process in the interconnecting layer.