Proceedings of International Conference on Perovskite and Organic Photovoltaics and Optoelectronics (IPEROP19)
Publication date: 23rd October 2018
Solution-processed tandem solar cells, that stack two or more single junction subcells with different band gaps to harvest photons in the full solar spectrum more efficiently, have attracted increasing attention recently. Organic photovoltaics and perovskite solar cells are promising candidates for the top and/or middle subcells of tandem solar cells because the solar cells are able to capture visible and near-infrared photon energy. While PbS and PbSe colloidal quantum dots (CQDs) have been gaining much attention for short-wave infrared solar cells owing to their wide-range bandgap tunability and solution process compatibility. Thus, we have focused on PbS QD/ZnO nanowire (NW) structures with the aim of achieving efficient carrier transport and light absorption in the infrared region simultaneously [1,2]. We then investigated the performance of PbS QD/ZnO NW solar cells using PbS CQDs with the first exciton absorption peak locating in the infrared region (940 nm-1840 nm) [3]. We recently constructed high efficiency infrared PbS QD/ZnO NW solar cells with a record high EQE of 47% (at 1560 nm). Based on these results, we will discuss the potential of PbS QD/ZnO NW solar cells for the middle and/or bottom subcells of solution-processed tandem solar cells.
This work was supported as part of the International Joint Research Program for Innovative Energy Technology funded by the Ministry of Economy, Trade and Industry (METI), Japan, and by the New Energy and Industrial Technology Development Organization (NEDO).