Study on mechanical, electronic and optical properties of Pb-free double halide perovskites In2TiX6 (X = Cl, Br, I) for solar cells based on first-principles

Importance of spin‐orbit coupling on photovoltaic properties of Pb‐free vacancy ordered double perovskites halides X 2 TeY 6 ( X = Cs , Rb , and Y = I , Br , Dahbi1, Tahiri2, Bounagui3 et al. 2022Intl J of Energy Research43030View full textAdd to dashboardCite

“…46 Otherwise, the TDOS and PDOS of X 2 TeY 6 have similar profiles with and without SOC, but only the lowest unoccupied molecular orbital (LUMO) is shifted toward the Fermi Level (E F ) which results in the forbidden band reduction in all cases due to SOC effects. Further, the 5p 5 /4p 5 /3p 5 states of I/Br/Cl hybridize with 5s 2 and 5p 4 states of Te in the upper valence band (VB) while the bottom conduction band (CB) is primly occupied by 5p 4 Te states and 5p 5 /4p 5 /3p 5 states of I/Br/Cl. Meanwhile, Figure 3 demonstrates that the highest occupied molecular orbital (HOMO) of all studies compounds (X 2 TeY 6 ) lie at W (0.5, 0.25, 0.75) high-symmetry point while the LUMO lie at L (0.5, 0.5, 0.5) high-symmetry point in the first Brillouin zone, thus X 2 TeY 6 DPHs exhibit indirect forbidden bands behaviors in W !…”

“…Over the past decades, the sources of fossil fuels diminish and energy demand increased due to the significant economic and population growth. Hence, the scientific communities have pushed to find alternatives to fossil fuel sources to limit climate change and for the use of endless energy sources 1‐5 . Solar energy is endless, clean and the cheapest power source in history 1‐3,6 .…”

“…Solar energy is endless, clean and the cheapest power source in history 1‐3,6 . Therefore, solar energy is the long‐term and cheap replacement of electricity produced from crude oil 1,4 . Halide perovskites (HPs) solar cells are attracting widespread interest from the scientific community because they have been proved as considerable light absorbers, 7‐10 they have a high‐power conversion efficiency (PCE) 4,11 and simple manufacturing process 9,11 .…”

“…[1][2][3]6 Therefore, solar energy is the long-term and cheap replacement of electricity produced from crude oil. 1,4 Halide perovskites (HPs) solar cells are attracting widespread interest from the scientific community because they have been proved as considerable light absorbers, [7][8][9][10] they have a high-power conversion efficiency (PCE) 4,11 and simple manufacturing process. 9,11 Moreover, the high PCE of perovskite solar cells are composed of lead (Pb) which are rapidly enhanced from 3.8% in 2009 to 25.5 ± 0.8% in 2021.…”

“…The absorption coefficient, reflectivity, and transmittance of X 2 TeY 6 (X = Cs and Rb; Y = I, Br, and Cl) contrition in the upper VB is from 5p4 Te states. Meanwhile, the band's structures ensured that the inclusion of SOC is necessary to have the correct characterization of the CB of X 2 TeY 6 compounds.…”