Authors: Kee-Jeong Yang, Sammi Kim, Se-Yun Kim, Kwangseok Ahn, Dae-Ho Son, Seung-Hyun Kim, Sang-Ju Lee, Young-Ill Kim, Si-Nae Park, Shi-Joon Sung, Dae-Hwan Kim, Temujin Enkhbat, JunHo Kim, Chan-Wook Jeon, Jin-Kyu Kang
Published: 2019-07-04
DOI: 10.1038/s41467-019-10890-x
Source: Full article
AbstractFor kesterite copper zinc tin sulfide/selenide (CZTSSe) solar cells to enter the market, in addition to efficiency improvements, the technological capability to produce flexible and large-area modules with homogeneous properties is necessary. Here, we report a greater than 10% efficiency for a cell area of approximately 0.5 cm2 and a greater than 8% efficiency for a cell area larger than 2 cm2 of certified flexible CZTSSe solar cells. By designing a thin and multi-layered precursor structure, the formation of defects and defect clusters, particularly tin-related donor defects, is controlled, and the open circuit voltage value is enhanced. Using statistical analysis, we verify that the cell-to-cell and within-cell uniformity characteristics are improved. This study reports the highest efficiency so far for flexible CZTSSe solar cells with small and large areas. These results also present methods for improving the efficiency and enlarging the cell area.