Microstructural and Optoelectronic Characterization of Hybrid Lead Mixed Halide Films CH3NH3PbI3-xClx Synthesized by Antisolvent Method

Abstract

As the energy industry advances, perovskite solar cells emerge as potential successors in solar technology. Researchers are focusing on enhancing the stability and performance of hybrid lead halide perovskite CH3NH3PbI3. One promising research direction is the use of hybrid lead mixed halide perovskite CH3NH3PbI3??Cl?. Adding the chlorine element helps stabilize the perovskite's phase by reducing the lattice constant and improving the carrier diffusion length. In this study, we fabricated perovskite films CH3NH3PbI3-xClx using the spin coating method combined with the antisolvent chlorobenzene. The synthesized films were dried at different temperatures. The microstructural and optoelectronic properties of the films were studied and evaluated by scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and ultraviolet-visible spectroscopy. The Tauc plot method used ultraviolet-visible absorption spectroscopy to determine the energy bandgap of materials. Experimental results have shown that incorporating chlorobenzene leads to the formation of perovskite crystals with a uniform size. Controlling the annealing temperature allows for precise management of film growth during synthesis. The perovskite film annealed at 100 °C exhibits tetragonal structures, with a particle size of 500 nm and high surface coverage. This film demonstrates the capability to absorb light up to 820 nm, with a bandgap energy reaching 1.5 eV, indicating an improvement compared to traditional CH3NH3PbI3 films. These results indicate the potential of this approach in producing perovskite films CH3NH3PbI3??Cl? as an absorber layer in solar cells, offering both high efficiency and cost effectiveness. In order to develop advanced solar panels that can supplant silicon cells, further investigation is imperative to enhance durability and manufacturing capabilities.