Influence of molybdenum and technetium doping on visible light absorption, optical and electronic properties of lead-free perovskite CsSnBr₃for optoelectronic applications

Abstract

In this study, the metal doping enhanced the optoelectronic properties of lead-free perovskite CsSnBr3; hence CsSn0.875Tc0.125Br3 is promising for solar cells and other optoelectronic applications.

Understanding the role of rare-earth metal doping on the electronic structure and optical characteristics of ZnO

“…The imaginary part of all samples' dielectric functions becomes zero at 40 eV, whereas the real part approaches unity. The occurrence of a sharp peak in the visible area of the real and imaginary parts of the dielectric function of the group (1) RE doped sample means that high absorption exists in this region, 56,79,80 which verifies our computed absorption spectra of RE-doped ZnO as seen in Fig. 3(a and b).…”

“…The doping effect causes the Fermi level to be moved toward the conduction band in the doped samples, which is a considerable difference between the pure and doped samples. 55,56,79,80 The Gd-4f, Eu-4f, Sm-4f, Pm-4f, Nd-4f, Pr-4f, Ce-4f, and La-5d states for Gd, Eu, Sm, Pm, Pm, Nd, Pr, Ce, and La-doped samples, respectively, are primarily responsible for the additional peaks detected in the TDOS of the dopant samples. The dopant contribution at the lower part of the conduction band leads to the change in the bandgap, and hence dopant energy states are introduced inside the bandgap, called the impurity states as depicted in Fig.…”

“…55,57,79,80 Photocatalysis is of special importance since it creates an environment for both oxidation and reduction conditions at the same time. 55,57,79,80 In this section, the key optical properties of pure and RE-doped ZnO, such as absorption coefficient, the real and imaginary parts of the dielectric function, optical conductivity, and reflectivity are quantified and discussed in detail which may aid in designing RE-doped photocatalytic, and solar cell systems with tailored optoelectronic properties. Firstly, the UV-visible absorption spectra of pure, RE alloyed ZnO samples are computed from the following equation: 64 ; herein, α ( ω ) is the absorption coefficient as a function of incident photon frequency, and ε 1 ( ω ) and ε 2 ( ω ) are the real, and imaginary parts of the dielectric function, respectively; and corresponding results are illustrated in Fig.…”

A comparative study of the mechanical stability, electronic, optical and photocatalytic properties of CsPbX3 (X = Cl, Br, I) by DFT calculations for optoelectronic applications

“…The real part of the dielectric function shows a higher value at low photon energy and then decreases rapidly with the increase of photon energy. It is well known that a perovskite material with such a higher value of the real part of the dielectric function exhibits a lower band gap, 127 which is also seen in the electronic band structure. On the other hand, the values of the imaginary part of the dielectric function decrease to zero at a higher photon energy region.…”

Ultra-violet to visible band gap engineering of cubic halide KCaCl3 perovskite under pressure for optoelectronic applications: insights from DFT

“…The analysis of a material's physical properties can be done by both experimental [1][2][3][4][5] and theoretical investigations. [6][7][8][9][10] Theoretical studies aid experimental work in gaining a better understanding of physical properties. 1,6 The physical properties of materials are associated with crystal structure.…”