Role of the chemical substitution on the structural and luminescence properties of the mixed halide perovskite thin MAPbI3−xBrx (0 ≤ x ≤ 1) films

Very high VOC and FF of CdTe thin‐film solar cells with the applications of organo‐metallic halide perovskite thin film as a hole transport layer

“…Figure 1B shows the XRD patterns monitored in the 2θ range of 10°–50° for MAPb(I 1‐x Br x ) 3 varying x from 0 to 1. As shown in the figure, as the Br concentration is increased, the diffraction peaks are shifted toward higher diffraction angles and matches very well with the previous reports 33,36,37 . The shift of diffraction angles is caused by decrease of lattice spacing due to the partial substitution of the larger (ionic radius of iodine 2.2 Å) iodine atom with a smaller (ionic radius of bromine 1.96 Å) bromine atom.…”

Influence of halide composition on the structural, electronic, and optical properties of mixedCH3NH3Pb(I1−xBrxJong1, Yu2, Ri3 et al. 2016Phys. Rev. B15311860View full textAdd to dashboardCite

“…where E g (0) and E g (1) are band gaps of MAPbI 3 (x=0) and MAPbBr 3 (x=1) respectively, and b is the so-called bowing parameter [34]. Our calculations gave the formula E g (x) = In order to directly estimate the light harvesting capability of PSCs, we next describe the photoabsorption coefficients of these mixed halide perovskites with different Br contents, which can be obtained from Equation (5) using the real and imaginary parts of frequency dependent dielectric constants, calculated within DFPT [42].…”

“…Once it is formed, however, the kinetic barrier may prevent the compound from phase separation, so that MAPbI 3 may still be stable for a certain period to be used safely in PSCs. In addition, they suggested a promising method to improve the stability of The most favorable attempt to improve the material instability of MAPbI 3 is to replace I ions with Br or Cl ions [31,33,34]. Noh et al [31] showed that increasing the Br content x in MAPb(I 1−x Br x ) 3 causes a phase transition, e.g., from tetragonal to cubic at x=0.13, and moreover altered the band gap following the quadratic function of Br content, E g (x) = 1.57+0.39x+0.33x 2 (eV).…”

Effect of guanidinium on the optical properties and structure of the methylammonium lead halide perovskite

“…the substitution of iodine by chloride or bromide atoms leads to a significant improvement of perovskite stability [24,25].…”