The characteristics of hole-transport material-free perovskite solar cells with carbon electrode made by using ion liquid methylammonium acetate solvent

Ion liquid is one of the eco-friendly solvent which has many special properties such as high viscosity, low vapor pressure and incombustibility and also has the polarity which can dissolve the perovskite precursor and thus it has a potency which can replace the toxic solvent including dimethylformamide (DMF) and dimethylsulfoxide (DMSO). This work researched the characteristics of perovskite and the influence on the performance of hole transport material-free perovskite solar cells with carbon electrode when we use ion liquid – methylammonium acetate (MAAc) as the solvent of precursor. Perovskite film prepared by using ion liquid is more even and denser than one using DMF and we could improve its crystallinity and increase the crystal size of perovskite. Analysis result shows that the nonradiative recombination of devices was decreased and the open circuit voltage could be improved when we using MAAc instead of DMF. The efficiency of device is 15.16%; higher than the control (13.18%) and especially its stability was maintained 90% of initial value after 1500 h without any seal when the relative humidity was 80%.