| 초록 |
We have fabricated inverted perovskite photovoltaics based on pH-controlled PEDOT:PSS hole transport layer (HTL). Recently, perovskite solar cells exhibit great potential, but the acidity of HTL limits the device performance and stability. In this study, the pH of HTL was adjusted, and photoactive perovskite crystals based on acid, neutral, and base HTL were compared via SEM, XRD, and GIWAXS, respectively, and device performances were systematically studied. As a result, neutral HTL improved external and internal quantum efficiency and led to excellent charge transport, resulting in 14.25% power conversion efficiency versus the acid based device (12.58%). It also shows consistent performance over a variety of active sizes by minimizing dependence on the light-absorb area by improving the quality of photoactive crystals. Finally, by preventing degradation due to strong acid, it maintains a fill factor even in a harsh environment (80% humidity), thereby improving fabrication stability. |
