A Comparative Study of Mechanical, Electronic, Optical, and Photocatalytic Properties of CsPbX₃ (X= Cl, Br, I) by DFT Calculations

Metal halide perovskites are attracted for next-generation optoelectronic devices but the stability issues hurdle in the path of commercial deployment. In this context, Cs-based perovskites are founded potential candidates for different applications. In this work, a comparative study of mechanical, electronic, optical, and photocatalytic properties of CsPbX₃ (X= Cl, Br, I) are performed by DFT calculations for the applicability of these materials in photocatalytic and optoelectronic devices with better agreements of damage-tolerance. Calculated lattice parameters and bandgaps are in good agreement with experimental data and some properties are found to be much better than other theoretical reports. It is evident that CsPbX₃ are suitable for green, orange, and red emissions respectively due to the proper bandgap. CsPbI₃ is the best photocatalyst for HER, and CsPbBr₃ is the most stable photocatalyst due to its nearly balanced oxidation and reduction potentials but CaPbCl₃ is better for O₂ production. Thus, our findings would be helpful for efficient electronic and optoelectronic device applications in addition to hydrogen production, biodegradation of polluted and waste materials.