Researchers have been able to successfully replace the expensive metal layer of the top electrode of perovskite solar cells with a less-expensive carbon-based electrode that can also be applied using roll-to-roll techniques. This new electrode deposition method involves the deposition of carbon and silver on a detachable plastic (PET) substrate first, with the dried electrode then pressed onto the top of the perovskite solar cell. The PET layer is then removed and can be reused.