Efficient and non-hysteresis CH3NH3PbI3/PCBM planar heterojunction solar cells

Abstract Highly efficient and non-hysteresis organic/perovskite planar heterojunction solar cells was fabricated by low-temperature, solution-processed method with a structure of ITO/PEDOT:PSS/CH 3 NH 3 PbI 3 /PCBM/Al. The high-quality perovskite thin film was obtained using a solvent-induced-fast-crystallization deposition involving spin-coating the CH 3 NH 3 PbI 3 solution followed by top-dropping chlorobenzene with an accurate control to induce the crystallization, which results in highly crystalline, pinhole-free, and smooth perovskite thin film. Furthermore, it was found that the molar ratio of CH 3 NH 3 I to PbI 2 greatly influence the properties of CH 3 NH 3 PbI 3 film and the device performance. The equimolar or excess PbI 2 was facile to form a flat CH 3 NH 3 PbI 3 film and produced relatively uniform perovskite crystals. Perovskite solar cells (PSCs) with high-quality CH 3 NH 3 PbI 3 thin film showed good performance and excellent repeatability. The power conversion efficiency ( PCE ) up to 13.49% was achieved, which is one of the highest PCEs obtained for low-temperature, solution-processed planar perovskite solar cells based on the structure ITO/PEDOT:PSS/CH 3 NH 3 PbI 3 /PC 61 BM/Al. More importantly, PSCs fabricated using this method didn’t show obvious hysteresis under different scan direction and speed.