Relationship between structure and optoelectrical properties of organic–inorganic hybrid materials containing fullerene derivatives

Novel lead iodide-based layered perovskite compounds, which contain fullerene derivatives, N-methyl-2-(4-ammoniumphenyl)-fulleropyrrolidine iodide (AmPF) and N-(n-dodecyl)-2-(4-ammoniumphenyl)-fulleropyrrolidine iodide (C12AmPF), in their organic layers were fabricated as thin solid films by spin-coating. The XRD profiles showed that (AmPF)PbI4 molecules were arranged in a closer-packing form, compared with (C12AmPF)PbI4. The photoluminescence spectra of thin films suggested the presence of energy transfer between C60 moiety and lead(II) iodide layers, which led to the disappearance of fluorescence peak at 517 nm and the appearance of a new fluorescence peak at 780 nm. (AmPF)PbI4 and (C12AmPF)PbI4 films exhibited photoconductivity when ultraviolet light was irradiated, and the photocurrent values with applying 1.0 V bias voltage were 1.77 μA and 1.48 × 10−2 μA, respectively.