Synthesis, characterization, and comparative study of titanium dioxide and methyl ammonium lead iodide perovskite doped with cesium

Undoped titanium dioxide (TiO₂) films were successfully doped with cationic cesium (Cs⁺) at different molar concentrations on a glass substrate via a two-step spin coating method. Undoped and cesium-doped methylammonium lead iodide (CH₃NH₃PbI₃) materials were prepared and deposited on the titanium dioxide films via a one-step spin coating process. The structure, morphology, elemental, and optical characteristics of the synthesized materials were respectively studied using X-ray diffractometer, scanning electron microscope, energy dispersive X-ray spectrophotometer (EDX), and ultraviolet–visible spectroscope. The structural result revealed crystalline peaks which became more prominent at increasing dopant concentration. Clustered nanospheres were observed from the morphological results with the presence of agglomerates. EDX results showed the presence of basic elemental constituents for the undoped and doped samples which confirms the deposition of the as-deposited elements. The optical results of the films showed good features with energy band gap values ranging from 2.03 eV to 1.98 eV for the undoped and doped samples. The prepared films are potentially applied in optical and solar cell devices.