The growth of FA-based mixed halide perovskite single-crystal via the ITC method has been investigated and characterized to detect its photosensitive properties. The photophysical, responsivity and detectivity also has been investigated.

Organic–inorganic hybrid lead halide perovskites have shown significant progress in the last few years having achieved efficiencies over 25% at the lab scale. The sequential deposition technique has provided a robust approach in the perovskite film fabrication. However, obtaining a reproducible and quality perovskite film has always been challenging because of the highly crystalline and ordered (001) oriented underlying PbI₂ film. Here, we report a simple solution approach to fabricate a PbI₂ residue-free, superior grade perovskite film by using a compositional engineered PbI₂–precursor solution. We demonstrate that the Pb–precursor film crystallized into a R-centered Hexagonal metric lattice with (h0l), (hk0), and (00l) orientations provides a more efficient and quicker conversion into perovskites compared to conventional (001) oriented 2H-PbI₂. A porous and multi-oriented PbI₂ film is prepared by rationally incorporating a volumetric fraction of Pb(Ac)₂·3H₂O in the typical PbI₂/dimethylformamide precursor solution, which significantly improves the surface features of PbI₂ as well as the structural properties. As a result, a compact, smooth, and large grain perovskite can be obtained by accomplishing a full conversion with comparatively much less reaction time. Furthermore, a comprehensive mechanism of structural modification of PbI₂ and the role of its orientation in ameliorating the reaction kinetics has been demonstrated.