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The potential utility of nanocrystals (NCs) based on cesium lead halide (CsPbX3, X= Cl, Br, and I) for various domains like optoelectronic and solar cells have driven a lot of interest in broadening the span of their exotic, unique and useful properties by tailoring the physical and chemical nature. In this communication, we have done the synthesis and characterization of the NCs to study the effect of Mn dopant in CsPbBr3. Structural parameters of the synthesized compounds have been characterized by using the X-ray diffraction (XRD) technique while electronic and photophysical characterization was done by using Photoluminescence (PL) spectroscopy. The structural characterization of the synthesized sample shows decrement in the lattice parameter due to the incorporation of Mn as the dopant in CsPbBr3. The experimentally calculated values of lattice parameters for CsPbBr3 and doped CsPbBr3 are found as 5.723 Å and 5.695 Å respectively. These results indicate a reduction in the lattice parameter due to the introduction of the Mn dopant in CsPbBr3. Also, XRD patterns confirm the cubic morphology of the synthesized samples. Understanding of photophysics and electron behavior has been done using PL of the synthesized samples and PL pattern shows a high-intensity peak around 520 nm and 510 nm for CsPbBr3 and doped CsPbBr3 respectively. PL results indicate the blue shift phenomena because of the Mn dopant in the CsPbBr3 sample. Also, the PL pattern shows small full-width half maxima (FWHM) for both samples which clearly suggests the homogeneity and orderness of the synthesized NCs. The experimentally calculated bandgap from PL pattern for CsPbBr3 and its doped version are found as 2.384 eV and 2.431 eV respectively. Also, the computer experiment has been done to scientifically envisage and understand the structural and electronic nature of our synthesized NCs. Plane-wave density functional theory (DFT) based computations have been performed to validate the experimentally characterized results of the synthesized NCs. Structural computations are done by optimizing the crystal structures of CsPbBr3 and its doped version. The theoretically computed lattice parameters after geometrical optimization (before optimization) for CsPbBr3 and doped CsPbBr3 are 5.731 Å (5.742 Å) and 5.705 Å (5.687 Å) respectively which also confirms the reduction in the lattice parameters after introducing Mn dopant in CsPbBr3. Computed lattice parameters also indicate the cubic crystal nature of both CsPbBr3 and its doped version and these computationally obtained structural properties show consistency with the experimental results. Further, the electronic behavior has been studied in a framework of DFT by calculating the band structure of the CsPbBr3 and its doped version. Band structure of CsPbBr3 and its doped version shows direct bandgap nature with valence band maxima (VBM) and conduction band minima (CBM) at the Gamma (Γ) point. The calculated direct bandgap for the undoped and doped NCs is 2.372 eV and 2.445 eV respectively. These results show very good agreement with the PL characterized results. This work successfully investigated the effect of Mn dopant in CsPbBr3 NCs showing fascinating nature for the applications in the area of light-emitting diodes (LEDs) and photovoltaics.
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