Strain-mediated electronic and optoelectronic attributes of cubic MAPbCl3 perovskites: A first-principles viewpoint

Owing to excellent optoelectronic features, organic-inorganic lead halide hybrid perovskite MAPbCl 3 is regarded as one of the most appealing possibilities for use in UV photodetectors and optoelectronic devices. This work comprehensively examined the structural, electronic properties, and photovoltaic applications of MAPbCl 3 perovskites under strains, applying the density functional theory based on first principles. At a high symmetry point R, the relaxed cubic MAPbCl 3 perovskite structure presents a direct bandgap of 3.18 eV and behaves as wide bandgap semiconductor. Fortunately, the bandgap lowering and/or raising to this perovskite can be adjusted by adding external biaxial strains. At stain −2%, the energy gap became 2.69 eV, which is 15.40% lower than before. When tested under tensile strains, MAPbCl 3 perovskites show a relatively smaller bandgap in WBG semiconductor characteristics. The valence bands and the conduction bands of MAPbCl 3 perovskite structures are regulated by Cl-p orbitals and Pb-p orbitals, respectively, as seen through the density of states (DOS), projected density of states (PDOS) and total density of states (TDOS) analysis. Furthermore, the redshift behaviour of both real and imaginary dielectric functions and the absorption coefficient spectra are observed in the photon energy spectrum (maximum at approximately 7.8 eV) as an impact of an increase in tensile strains (under −2%) and blue-shift for compressive strains. The optical studies show that the MAPbCl 3 perovskites have significant photon energy absorption capabilities in the ultraviolet regions. The strain-dependent optoelectronic properties of MAPbCl 3 perovskites will support their future applications in optoelectronics and photovoltaic cell fabrication.