Electronic and optical properties of bulk and surface of CsPbBr3 inorganic halide perovskite a first principles DFT 1/2 approach

Abstract

This work aims to test the effectiveness of newly developed DFT-1/2 functional in calculating the electronic and optical properties of inorganic lead halide perovskites CsPbBr3. Herein, from DFT-1/2 we have obtained the direct band gap of 2.36 eV and 3.82 eV for orthorhombic bulk and 001-surface, respectively. The calculated energy band gap is in qualitative agreement with the experimental findings. The bandgap of ultra-thin film of CsPbBr3 is found to be 3.82 eV, which is more than the expected range 1.23-3.10 eV. However, we have found that the bandgap can be reduced by increasing the surface thickness. Thus, the system under investigation looks promising for optoelectronic and photocatalysis applications, due to the bandgap matching and high optical absorption in UV–Vis (Ultra violet and visible spectrum) range of electro-magnetic(em) radiation.

Kinetic analysis of the growth behavior of perovskite CsPbBr3 nanocrystals in a microfluidic system

“…It is known that bulk CsPbBr 3 can be presented in an orthorhombic, tetragonal and cubic structure in the temperature range of 0 to 353 K, 273 to 403 K and 403 K above, respectively. 63 That is to say, bulk CsPbBr 3 can be seldom presented in a cubic structure at 0 K. To estimate the numerical value of E 0 for cubic CsPbBr 3 at 0 K, we linearly extrapolate the numerical results given by Mannino et al 64 and obtain E 0 ≈ 2.29 eV.…”

Stabilization of CsPbBr3quantum dots for photocatalysis, imaging and optical sensing in water and biological medium: a review

“…CPQDs exhibit several interesting electrical and optical properties that are best suited for the utilization of solar energy like long charge carrier diffusion lengths, 140 a high absorption coefficient 141 and shallow energy states from intrinsic defects. The relative positions of the CPQD conduction band (CB) and valence band (VB) are depicted with the redox potentials in Fig.…”

“…With the required characteristics for photocatalysis, 138 CPQDs qualify themselves as a good photocatalytic material with an apt electronic structure and a band gap of 2.3 eV. 139 CPQDs exhibit several interesting electrical and optical properties that are best suited for the utilization of solar energy like long charge carrier diffusion lengths, 140 coefficient 141 and shallow energy states from intrinsic defects. The relative positions of the CPQD conduction band (CB) and valence band (VB) are depicted with the redox potentials in Fig.…”

Aqueous, Non-Polymer-Based Perovskite Quantum Dots for Bioimaging: Conserving Fluorescence and Long-Term Stability via Simple and Robust Synthesis

“…However, their strong quantum confinement adversely increases their transition probability, enhances spectral broadening, and also adds to the high density of trap states (due to their large surface-to-volume ratio) . To overcome these limitations, the use of perovskite quantum dots (PQDs) has seen increased interest, especially due to their unique physicochemical properties. , For example, PQDs exhibit strong excitonic photoluminescence even when the charge carriers are weakly confined, and their excitonic transition energy is less sensitive to the size of the quantum dot. , When PQDs are used as fluorescent probes, they offer excellent quantum yields (up to 90%) with narrow full width at half-maximum, which enables highly sensitive and rapid detection . They are attractive for advanced fluorescence biological applications such as ultrahigh resolution bioimaging, biosensing, and flow cytometry. , However, to date PQDs have had limited biological applications , because they are well known to have poor stability when exposed to moisture, light, or heat due to their low formation energy and dynamic ligand binding to the crystal surface …”