Color tunable nanopaper solar cells using hybrid CH3NH3PbI3−xBrx perovskite

We demonstrate a flexible solar cell by combining nanopaper and perovskite, which are used as the substrate and light absorber, respectively. Since nanopaper is made of the porous nanofiber, they should be is the high transmittance and haze property. Paper substrates have drawn interest for the application flexible devices due to high thermal expansion coefficient compared to conventional plastic substrates and can be disposed as environmental waste. The conductive electrode consisting of three alternating layers (TiOx/Ag/TiOx, DMD) on nanopaper was prepared by sputtering deposition. We introduced mixed halide perovskite (CH3NH3PbI3−xBrx) into DMD structure on nanopaper to change color of solar cell from dark brown to yellow. We expect that the presented solar cell would give not only a new candidate of the environmental solar system but also excellent durable and stable solar cells with low cost.