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The 2,4,5-Triphenyl Imidazole (TPI) C21H16N2 samples were deposited as thin film by means of the physical vapor deposition (PVD) on glass and silicon substrates. As well as, three solutions with different concentrations using dimethyl sulfoxide (DMSO) solvent. The physical properties of all samples were investigated using different techniques. The thin film's morphology was examined using atomic force microscopy (AFM) of the sample on silicon substrates, revealing a highly rough surface. The optical characteristics of both the thin film on glass substrate, the solutions, and the powder were studied through transmittance and absorbance measurements, which helped determine a value of the band gap of 3.45 eV. Photoluminescence and thermal photoluminescence spectroscopy showed the high emission of the material in its different aspects. Theoretical simulations of the HOMO–LUMO gap and electronic absorption spectra were obtained using the density functional theory (DFT) approach. [ABSTRACT FROM AUTHOR]

This article covers selected properties of organic–inorganic thin films of hybrid perovskites with the summary formulas CH3NH3MI3, where M = Pb, Cd, Ge, Sn, Zn. The paper discusses not only the history, general structure, applications of perovskites and the basics of the theory of nonlinear optics, but also the results of experimental research on their structural, spectroscopic, and nonlinear optical properties. The samples used in all presented studies were prepared in the physical vapor deposition process by using co-deposition from two independent thermal sources containing the organic and inorganic parts of individual perovskites. Ultimately, thin layers with a thickness of the order of nanometers were obtained on glass and crystalline substrates. Their structural properties were characterized by atomic force microscopy imaging. Spectroscopic tests were used to confirm the tested films' transmission quality and determine previously unknown physical parameters, such as the absorption coefficient and refractive index. Experimental results of the nonlinear optical properties were obtained by studying the second and third harmonic generation processes and using initial sample polarization in the so-called Corona poling process. The obtained experimental results allowed us to determine the second- and third-order nonlinear optical susceptibility of the tested materials. [ABSTRACT FROM AUTHOR]

The elaboration and characterization of Cz-P(2,7) in solution and as thin films are the main topics of this work based on a carbazole unit for perovskite solar cells. Our study focuses on studying optical properties. The elaboration of thin films was performed using sol–gel spin-coating onto a glass substrate. Thin films deposited from different solvents were characterized by UV−vis and photoluminescence spectroscopy. The absorption maxima of the investigated compounds are not significantly shifted with different solvents. The result of photoluminescence shows a green-yellow emission. The optical studies revealed that the investigated material can be a promising material for the development of perovskite solar cells. [ABSTRACT FROM AUTHOR]

In this work, we explore a new experimental study of Barium oxide (BaO) thin films, fabricated using the physical vapor deposition (PVD) technique on both glass and silicon substrates. The BaO thin films have emerged as highly adaptable materials with immense potential across multiple technological domains. The investigation focuses on the morphological, optical, and electrical properties of BaO thin films to determine their potential for various applications. These films, consistently tailored to a thickness of 100 nm, exhibit exceptional optical properties, boasting an impressive transmittance rate of up to 90%. This makes them exceptionally well-suited for applications that demand superior optical transmission, such as flat-panel displays, photovoltaic devices, and various optoelectronic applications. The films' low roughness values, measured at 6.31 nm for glass-deposited films and 13.32 nm for silicone-deposited ones, underscore their uniformity, ensuring stable and precise performance control in diverse applications. Further underscoring their versatility is the wide energy gap of 2.93 eV, suggesting their potential utility in advanced optoelectronic devices that require higher energy levels. In addition to their optical prowess, BaO thin films exhibit impressive electrical resistance, measuring at 3.3 × 108 ohms, rendering them promising candidates for specialized applications, including pressure and humidity sensors, as well as electrical insulation devices. Overall, these films represent an exciting avenue for addressing specific technological needs and driving innovation in the realm of thin film technology. [ABSTRACT FROM AUTHOR]

In this work, a novel experimental investigation of photoluminescence properties of Znq2 thin films co-doped with different concentrations of DCM were performed. The thin films were successfully deposited on glass substrates with different compositions, under high vacuum, by using the vacuum evaporation technique. For all compositions, the photoluminescence was measured at room temperature and also at low temperature in a wide range from 77 to 300 K with a step of 25 K in a high vacuum. The lifetime of the sample studied in real time was also measured using the decay time technique. The results obtained confirm that the doping influences the intensity of the DCM photoluminescence and also shows a complete energy transfer occurred from Znq2 to DCM which may have shifted the photoluminescence peak from Znq2 to the orange wavelength region which is related to DCM. The lifetime of the sample studied in real time was about 4.47 ns for Znq2 and while all the other samples showed two decay time components. As a result, the doping influences the optical properties of Znq2 and makes it a potential candidate for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Benzonitrile derivatives (BDs) are very promising for applications in materials science, photonics, and optoelectronics due to their intriguing electronic and optical properties. This study comprehensively investigates BDs, aiming to uncover their fundamental characteristics and potential applications. Using advanced theoretical techniques like Gaussian software, it is gained unprecedented insights into the photoinduced isomerization phenomenon for all‐optical switching in these compounds. The theoretical framework clarifies molecular transition states and explores a range of properties, providing a comprehensive understanding of BDs. Empirical data on the emission properties of BDs, from fluorescence analyses in liquid solutions to light amplification in solid‐state PMMA thin films, complement the theoretical examinations. Notably, white light emission from a single benzonitrile compound is achieved, showcasing its potential for data transmission through Li‐Fi technology. Finally, the all‐optical switching phenomenon in BDs using 3rd order nonlinear optical effects is experimentally validated. This complementary and comprehensive study advances understanding of BDs and demonstrates their potential for practical applications in emerging photonic and optoelectronic technologies. [ABSTRACT FROM AUTHOR]

In this paper, we present the third harmonic generation response of Znq2 (Bis-(8-hydroxyquinolinato)zinc), Cuq2 (8-Hydroxyquinoline copper(II)), and Alq3 (Tris-(8-hydroxyquinoline)aluminum) organometallic compounds. An experiment was conducted for s and p polarizations of incident beam, using the Maker fringes technique. The third order nonlinear susceptibility χ(3) was estimated using the Kubodera and Kobayashi comparative model, on the grounds that presented compounds exhibit high linear absorption of the generated third harmonic wavelength (355 nm). These complexes were deposited as thin films using the physical vapor deposition (PVD) method. Investigated complexes vary in terms of the coordination center and number of quinoline ligands, which visibly influence their nonlinear response. The global hybrid B3LYP functional with the basis set 6-31G(d) was used in computing the linear and non-linear optical properties. The computed γtot value (8765.36 × 10−36 esu for Cuq2) is superior to that of methylene blue (γ = 32.00 × 10−36 esu). The calculated theoretical values were found to be in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

• HTM2 thin films were elaborated using the Physical vapor deposition method. • The characterization has been done by AFM, MEB, UV–VIS, PL spectra, and decay. • HTM2 exhibited a homogeneous surface with good absorption in the UV region. • The experimental results were validated using DFT calculations. • HTM2 can be applied as a potential HTM for perovskite solar cells. This paper presents the development of a dopant-free HTM as a thin film, utilizing carbazole (2,7) as a central building block. The deposition of homogeneous thin films of HTM2 was successfully achieved through Physical Vapor Deposition. The morphological, optical, and electrical properties of the fabricated samples were extensively studied using techniques such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), UV–visible spectroscopy, and Photoluminescence Technique. The AFM and SEM analyses demonstrated the uniformity and flatness of the thin film surfaces. The UV spectra results indicated that the maximum absorption spectra did not exhibit significant shifts when measured in chlorobenzene solvent, with an estimated band gap of approximately 2.96 eV. Photoluminescence spectroscopy and decay time measurements were conducted on HTM2 thin films, which revealed emission in the green-yellow region. The photoluminescence spectra of the thin films exhibited red-shifted emission bands compared to the solution, attributable to stronger π-π intermolecular interactions resulting in the closeness of the molecules in the solid state. This work finally couples the theoretical and experimental results to validate our obtained results and to get an idea about the efficiency of the cell-based HTM2. The obtained results confirmed that the investigated material can find applications in perovskite solar cells. [ABSTRACT FROM AUTHOR]

In the present work, investigations on the second and third-order NLO properties of, 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) reddye co-doped bis(8-hydroxyquinoline) Zinc (Znq 2) thin films with different concentrations were investigated. The samples have a thickness of 100 nm. They were prepared using the physical vapor deposition (PVD) method under a high vacuum. The morphological properties were studied by atomic force microscopy. The second-order nonlinear susceptibility χ(2) after applying the corona poling technique was estimated using the comparative model of Lee, while the third-order nonlinear susceptibility χ(3) was estimated using the comparative model of Kubodera and Kobayashi. The tested samples varied in terms of the concentration of DCM in the structure, which visibly influenced their nonlinear response. The pure DCM thin film showed a large value of the second and third-order nonlinear susceptibility, while pure Znq 2 had only the second harmonic response with a low value. In this study, we have demonstrated that doping with DCM, even with small concentrations, has also strongly enhanced the non-linearity of Znq 2. The obtained results show that such compositions can be a good alternative for optoelectronic applications. [Display omitted] • Preparation of Thin Films of DCM co-doped Znq 2 by co-deposition PVD method. • Study of the second and third harmonic generation of DCM-Znq 2 thin films. • Control of NLO second and third order susceptibility values due to film's composition. [ABSTRACT FROM AUTHOR]

A simple carbazole-based hole transport material, termed HTM1, has been deposited as thin films. The samples were elaborated via a Physical Vapor Deposition to ensure the production of high-quality thin films. The study of the morphological and photophysical properties of the investigated compound was revealed through Scanning Electron Microscopy, Atomic Force Microscopy, Ultraviolet–Visible, and Photoluminescence spectroscopy. A flat surface with low roughness values was observed in the SEM and AFM images. Moreover, the obtained films revealed a higher absorption in the UV region. Optical parameters such as the energy gap (2.9 eV) and refractive index were determined using transmittance measurements. The temperature-dependent photoluminescence over a range of 77–300 K has also been investigated. It is found that, as the temperature decreases, a new emission band appears, which may be due to the formation of excimers. Added to that, theoretical investigation of the highest occupied molecular orbital, the lowest unoccupied molecular orbital, the density of states, and the optical energy gap were studied using density functional theory (DFT) with the hybrid B3LYP exchange-correlation function and the 6-311G (d,p) basis set. Absorption spectra was generated using the TD-DFT method. The absorption maximum obtained (398 nm) for HTM1 closely matched with the experimental value (393 nm). Following these characterizations, simulation studies on the photovoltaic performances of the HTM1 for perovskite solar cells have been done. This cell provided a maximum PCE of 21.31%. [ABSTRACT FROM AUTHOR]

In this study, zinc sulfide (ZnS) thin films were deposited via physical vapor deposition (PVD) under high vacuum conditions, incorporating dual dopants manganese (Mn2+) and calcium (Ca2+). Morphological examination by AFM revealed that Mn2+ promoted a uniform and smooth film structure, whereas Ca2+ induced surface roughness. Optical characterization using ultraviolet–visible spectroscopy showed high transparency in the visible range, with doping leading to significant alterations in the bandgap energy. Photoluminescence investigations displayed prominent emission peaks at 385 nm, 448 nm, and 560 nm, characteristic of ZnS bandgap emissions, as well as an additional peak at 600 nm due to the novel dopant's influence. X-ray fluorescence (XRF) and Fourier transform infrared (FTIR) analyses verified the presence of ZnS and other constituents. Doping improved the optical and luminescent characteristics, offering potential for use in optoelectronics, light-emitting diodes (LEDs), and advanced technology development. This customizable approach to ZnS thin films presents innovative opportunities within material science and device manufacturing. • Fabricated thin films XS (X = Mn, Ca) By using PVD. • The morphological properties have been influenced by the doping. • Optical band gap values decrease by increasing the incorporation of Ca2+ in the film. • ZnS films doped with Mn/Ca exhibit PL emissions at various wavelengths. [ABSTRACT FROM AUTHOR]