Figure 5From: Efficient perovskite solar cells based on low-temperature solution-processed (CH3NH3)PbI3 perovskite/CuInS2 planar heterojunctionsUV–vis absorption spectra of the ITO/CuInS 2 (1) and ITO/CuInS 2 ( n )/Al 2 O 3 /(CH 3 NH 3 )PbI 3 films ( n = 1, 2, and 3).Back to article page