The Determination of the Mechanical, Optoelectronic, Structural and Transport Attributes of Double Perovskite AInGaBr (A=K, Rb, Cs) Halides for Renewable Energies: A DFT Study.

Safer and more environmentally friendly alternatives to lead-based perovskites include lead-free halide perovskites, which retain good optoelectronic capabilities while reducing environmental toxicity. They also align better with ecological and regulatory standards for green technologies. In this manuscript, we have presented the first principles analysis of the physical traits of AInGaBr (A=K, Rb, Cs).

A DFT approach to correlate the physical characteristics of novel chalcopyrites ASbN(A = Li, Na) for green technology.

Semiconductor chalcopyrite compounds have been a subject of research interest due to their diverse range of physical properties that have captured the attention of scientists. In this ongoing research, we have examined the physical characteristics of LiSbN and NaSbN chalcopyrites using DFT. The modified Becke-Johnson (mBJ) potential is utilized for the computation of electronic structures.

Electronic Structure and Optical Properties of Inorganic and CsPbX (X = Cl, Br, I) Perovskite: A Theoretical Understanding from Density Functional Theory Calculations.

In this study, we investigated the optoelectronic properties of cubic () and orthorhombic () CsPbX (X = I, Br, and Cl). We utilized the full potential linear augmented plane wave method, which is implemented in the WIEN2k code, to facilitate the investigation. Different exchange potentials were used to analyze the optoelectronic behavior using the available density functional theory methods.

Surface Passivation for Promotes Bi-Excitonic Amplified Spontaneous Emission in CsPb(Br/Cl) Perovskite at Room Temperature.

Perovskite-type lead halides exhibit promising performances in optoelectronic applications, for which lasers are one of the most promising applications. Although the bulk structure has some advantages, perovskite has additional advantages at the nanoscale owing to its high crystallinity given by a lower trap density. Although the nanoscale can produce efficient light emission, its comparatively poor chemical and colloidal stability limits further development of devices based on this material.

Successful Growth of TiO Nanocrystals with {001} Facets for Solar Cells.

The growth of nanocrystals (NCs) from metal oxide-based substrates with exposed high-energy facets is of particular importance for many important applications, such as solar cells as photoanodes due to the high reactivity of these facets. The hydrothermal method remains a current trend for the synthesis of metal oxide nanostructures in general and titanium dioxide (TiO) in particular since the calcination of the resulting powder after the completion of the hydrothermal method no longer requires a high temperature. This work aims to use a rapid hydrothermal method to synthesize numerous TiO-NCs, namely, TiO nanosheets (TiO-NSs), TiO nanorods (TiO-NRs), and nanoparticles (TiO-NPs).

Conjugated Polymers-Based Ternary Hybrid toward Unique Photophysical Properties.

The improvement of optical and optoelectronic properties of the individual poly [2-methoxy-5- (2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), poly[2-methoxy-5-(3,7-dimethyl-octyloxy)-1,4-phenylenevinylene]-End capped with Dimethyl phenyl (OC1C10-PPV-DMP), and poly (9,9'-di- n -octylfluorenyl-2,7-diyl) (F8) was revealed by blending them in ternary hybrid with optimal ratio (F8/2 wt.% MEH-PPV/2 wt.% OC1C10-PPV-DMP).

Amplified Spontaneous Emission from Thermally Evaporated High-Quality Thin Films of CsPb(BrY) (Y = I, Cl) Perovskites.

As a wavelength-tunable lasing material, perovskites are now generating a lot of scientific attention. Conventional solution-processed CsPbX perovskite films sometimes suffer unavoidable pinhole defects and poor surface morphology, severely limiting their performance on amplified spontaneous emission (ASE) and lasing application. Herein, a thermal evaporation approach is explored in our work to achieve a uniform and high-coverage CsPb(BrY) (Y = I, Cl) perovskites polycrystalline thin film.

Controlling the Emission Spectrum of Binary Emitting Polymer Hybrids by a Systematic Doping Strategy via Förster Resonance Energy Transfer for White Emission.

Tuning the emission spectrum of both binary hybrids of poly (9,9'-di-n-octylfluorenyl-2,7-diyl) (PFO) with each poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) and poly[2-methoxy-5-(3,7-dimethyl-octyloxy)-1,4-phenylenevinylene] end-capped with Dimethyl phenyl (MDMO-PPV-DMP) by a systematic doping strategy was achieved. Both binary hybrid thin films of PFO/MEH-PPV and PFO/MDMO-PPV-DMP with various weight ratios were prepared via solution blending method prior to spin coating onto the glass substrates. The conjugation length of the PFO was tuned upon addition of acceptors (MEH-PPV or MDMO-PPV-DMP), as proved from shifting the emission and absorption peaks of the binary hybrids toward the acceptor in addition to enhancing the acceptor emission and reducing the absorbance of the PFO.

Density Functional Theory Analysis of Structural, Electronic, and Optical Properties of Mixed-Halide Orthorhombic Inorganic Perovskites.

Inorganic metal-halide perovskites hold a lot of promise for solar cells, light-emitting diodes, and lasers. A thorough investigation of their optoelectronic properties is ongoing. In this study, the accurate modified Becke Johnson generalized gradient approximation (mBJ-GGA) method without/with spin orbital coupling (SOC) implemented in the WIEN2k code was used to investigate the effect of mixed I/Br and Br/Cl on the electronic and optical properties of orthorhombic CsPb(I Br ) and CsPb(Br Cl ) perovskites, while the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) method was used to investigate their structural properties.

Enhancement of Light Amplification of CsPbBr Perovskite Quantum Dot Films via Surface Encapsulation by PMMA Polymer.

Photonic devices based on perovskite materials are considered promising alternatives for a wide range of these devices in the future because of their broad bandgaps and ability to contribute to light amplification. The current study investigates the possibility of improving the light amplification characteristics of CsPbBr perovskite quantum dot (PQD) films using the surface encapsulation technique. To further amplify emission within a perovskite layer, CsPbBr PQD films were sandwiched between two transparent layers of poly(methyl methacrylate) (PMMA) to create a highly flexible PMMA/PQD/PMMA waveguide film configuration.

Achieving Optical Gain of the CsPbBr Perovskite Quantum Dots and Influence of the Variable Stripe Length Method.

High-quality inorganic cesium lead halide perovskite quantum dot (CsPbBr PQD) thin films were successfully deposited directly from a powdered source and used as an active laser medium following the examination of their distinctive surface and structural properties. To determine the suitability of the CsPbBr PQDs as an active laser medium, amplified spontaneous emission (ASE) and optical gain properties were investigated under picosecond pulse excitation using the variable stripe length (VSL) method. The thin film of CsPbBr PQDs has exhibited a sufficient value of the optical absorption coefficient of ∼0.

Tuning Photophysical Properties of Donor/Acceptor Hybrid Thin- Film via Addition of SiO/TiO Nanocomposites.

The influence of SiO/TiO nanocomposites (STNCs) content on non-radiative energy transfer (Förster-type) from poly (9,9'-dioctylfluorene-2,7-diyl) (PFO) to poly [2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) using steady-state and time-resolved photoluminescence spectroscopies was investigated at room temperature. The improved energy transfer from PFO to MEH-PPV upon an increment of the STNCs was achieved by examining absorbance, emission (PL) and photoluminescence excitation (PLE) spectra. The shorter values of the quantum yield (φ) and lifetime (τ) of the PFO in the hybrid thin films compared with the pure PFO, indicating efficient energy transfer from PFO to MEH-PPV with the increment of STNCs in the hybrid.

Single-Source Thermal Evaporation Growth and the Tuning Surface Passivation Layer Thickness Effect in Enhanced Amplified Spontaneous Emission Properties of CsPb(BrCl) Perovskite Films.

High-quality inorganic cesium lead halide perovskite CsPb(BrCl) thin films were successfully achieved through evaporation of the precursors and deposition sequentially by a single-source thermal evaporation system. The different melting points of the precursors were enabled us to evaporate precursors one by one in one trip. The resulting films through its fabrication were smooth and pinhole-free.

Ultra-Stable Polycrystalline CsPbBr Perovskite-Polymer Composite Thin Disk for Light-Emitting Applications.

Organic-inorganic halide organometal perovskites have demonstrated very promising performance in optoelectronic applications, but their relatively poor chemical and colloidal stability hampers the further improvement of devices based on these materials. Perovskite material engineering is crucial for achieving high photoluminescence quantum yields (PLQYs) and long stability. Herein, these goals are attained by incorporating bulk-structure CsPbBr, which prevents colloidal degradation, into polymethyl methacrylate (PMMA) polymer in thin-disk form.

Fabrication of Thin Films from Powdered Cesium Lead Bromide (CsPbBr) Perovskite Quantum Dots for Coherent Green Light Emission.

High-quality thin films were obtained directly by spin-coating glass substrates with suspensions of powdered cesium lead bromide (CsPbBr) perovskite quantum dots (PQDs). The structural properties of the films were characterized via transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) analysis, and atomic force microscopy (AFM). The crystal structure of the CsPbBr PQDs was unique.

Structural, Electronic, and Optical Properties of CsPb(BrCl) Perovskite: First-Principles Study with PBE-GGA and mBJ-GGA Methods.

The effect of halide composition on the structural, electronic, and optical properties of CsPb(BrCl) perovskite was investigated in this study. When the chloride (Cl) content of x was increased, the unit cell volume decreased with a linear function. Theoretical X-ray diffraction analyses showed that the peak (at 2θ = 30.

Triplet Energy Transfer Mechanism of Ternary Organic Hybrid Thin Films of PFO/MEH-PPV/CsPbBr Perovskite Quantum Dots.

The triplet energy transfer mechanism of novel poly(9,9-di--octylflourenyl-2,7-diyl) (PFO)/poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV)/CsPbBr perovskite quantum dot (PQD) hybrid thin films was comprehensively investigated. The concentrations of PFO and MEH-PPV in all the specimens were fixed, while the PQD content was varied with various weight ratios and premixed by a solution blending method before it was spin-coated onto glass substrates. The triplet non-radiative Förster resonance energy transfers (FRETs) in the PFO/MEH-PPV/PQDs ternary blend, the dual FRET from PFO to both PQDs and MEH-PPV, and the secondary FRET from PQDs to MEH-PPV were observed.

Density Functional Study of Cubic, Tetragonal, and Orthorhombic CsPbBr Perovskite.

Cesium lead bromide (CsPbBr) perovskite has recently gained significance owing to its rapidly increasing performance when used for light-emitting devices. In this study, we used density functional theory to determine the structural, electronic, and optical properties of the cubic, tetragonal, and orthorhombic temperature-dependent phases of CsPbBr perovskite using the full-potential linear augmented plane wave method. The electronic properties of CsPbBr perovskite have been investigated by evaluating their changes upon exerting spin-orbit coupling (SOC).

Optical and structural properties of CsPbBr perovskite quantum dots/PFO polymer composite thin films.

The aim of this study is to investigate the optical and structural properties of polymer/perovskite quantum dots (QDs) composite thin films and estimate the applicability of using these blends as active materials in photonic devices. A solution has been utilized, which is processed based on conjugated polymer and perovskite QDs composite films. The incorporation of CsPbBr QDs, with various weight ratios, influences the structure of the thin films, as proven by several techniques.