We demonstrate series-connected hybrid tandem multijunction photovoltaics by combining hydrogenated amorphous silicon (a-Si:H) and polymer-based organic photovoltaics (OPVs). To utilize the wide solar spectrum with cost-effective processes, we employed a solution-processed low band gap OPV subcell onto the a-Si:H subcell. The interfacial contact between the subcells strongly affects the photovoltaic performance of the tandem cells. By using MoO3 as an efficient hole transporting intermediate layer instead of the conventional conducting polymer, we obtained power conversion efficiency of 1.84% and open-circuit voltage (VOC) of 1.50 V which corresponds closely to the sum of VOC s of the subcells.
Bibliographical noteFunding Information:
This research was supported by the Pioneer Research Center Program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (Grant No. 2009-0081500) and by KRCF (Korea Research Council of Fundamental Science and Technology) and KIST (Korea Institute of Science and Technology) for “NAP (National Agenda Project) program.”