Strain and layer modulated electronic and optical properties of low dimensional perovskite methylammonium lead iodide: Implications to solar cells

摘要

In the present work we report the effect of quantum confinement, biaxial and uniaxial strains on electronic properties of two dimensional (2D), one dimensional (1D) and layered system of Methylammonium lead iodide (MAPI) in cubic phase using first principles calculations based on density functional theory for its implications to solar cell. Our studies show that the bandgap of MAPI is dimension dependent and is maximum for 1D. We also found that the band gap of 2D MAPI can be modulated through application of biaxial strain, which shows linear relation with strain; compressive strain decreases the band gap whereas tensile strain increases the band gap. 1D MAPI shows near parabolic response towards strain which increases with compressive and tensile strain. Our studies show that the 2D MAPI is better for a solar cell due to lower effective mass of electron and hole arising from the strong s-p anti-bonding coupling. The calculated solar cell parameters suggest that the 2D MAPI is best suited for solar cell applications. The calculated open circuit voltage, fill factor and efficiency are highest for 2D MAPI. The highest theoretical efficiency of 2D MAPI is 23.6% with mesoporous (mp)-TiO2 electrode.