A comparative study of mixed halide perovskite thin film preparation by three- and two-step electrodeposition techniques

Nowadays, access to cheap, renewable and achievable energy sources is no longer just a dream with perovskite solar cells (PSCs). Reaching the record of ∼25% efficiency in 2019 has increasingly led researchers to address the challenges facing commercialization, including finding suitable large scale preparation techniques and increasing the lifetime of PSCs. According to various reports in the thin film solar cells fabrication based on electrodeposition (ED) routes, it is worth noting that the ED technique could be an interesting candidate for production of large-scale perovskite solar cells and low-cost modules in the future. Here, we compare the optoelectronic properties of the MAPb(IxBr1-x)3 perovskite layers (Eg = 1.9 eV) synthesized in three and two step based on ED-PbO2 layer on FTO (Fluorine-doped Tin Oxide) substrates. We show that the direct conversion of ED-PbO2 to perovskite, in addition to its cost-cutting and time-saving benefits, can lead to a uniform layer with significantly admirable structural properties compared to the conventional perovskite conversion using the 3-steps ED method. The measured external quantum efficiency (EQE) spectrum shows the photo-sensing capability of the 2-step ED perovskite layer in a wide range from ultraviolet to visible light region. The 2-step ED perovskite-based photodetector device exhibited superb performance, which resulted in high photo/dark current ratio of 107 at 1V under 660 nm (2000 μW power intensity) light illumination.