Abstract
Polymer solar cells (PSCs) have been attracting intensive research attention since 1980s, especially after the advancement brought by Tang et al. in 1986. Advantages of PSCs include their low manufacturing cost, low fabrication temperature and, mechanical flexibility, light weight and production process are solution based. In the past decades, different active layer materials for PSCs have been being developed and one of the latest is PTB7:PC71BM.
Another new type of solar cells is Hybrid Perovskite solar cells. They can be solution-processed, and their efficiencies achieved 17.9% in 2014, as a result, they are attracting attentions from virtually any material scientist who work on solar cell.
This study aims to characterise the optical properties of the active layer in the solar cells, including PTB7:PC71BM blend films and Perovskite films. The major tool is Spectroscopic Ellipsometry (SE) combined with transmission (T) measurement through which the optical properties (n,k) of thin films can be accurately determined. The results in this study are valuable for solar cell performance simulations and strategic planning of solar cell structures.