Luminescence feature of new 3,6‐di(thiazolidin‐5‐one‐2‐yl)‐carbazole derivative: synthesis, photophysical properties, density functional theory studies, and crystal shape effect

Abstract

A new carbazole chromophore conjugated with substituted thiazolidine-4-one (CzPT) was synthesized by applying the Knoevenagel reaction between 3,6-diformyl-Nhexylcarbazole and ethyl 2-aceto-2-(5-oxo-3-phenylthiazolidin-2-ylidene)acetate.The chemical structure of the new derivative (CzPT) was elucidated by spectral studies. The CzPT absorption spectra in different solvents exhibited a red shift for λ max by increasing solvent polarity. Bands at 430-474 nm appeared and were attributed to intramolecular charge transfer with high π-π* characteristics. CzPT fluorescence spectra exhibited a red shift after increasing the solvent polarity. To understand the Stokes' shift (Δ νÞ behaviour of the CzPT derivative referring to the polarity of solvents, Lippert-Mataga and linear solvation-energy relationship (LSER) models were employed in which the LSER exhibited respectable results compared with Lippert-Mataga (r 2 = 0.9707). Moreover, time-dependent density functional theory absorption spectra in hexane and dimethylformamide showed that λ max had a major contribution in the highest occupied molecular orbital to lowest unoccupied molecular orbital transition in both solvents. In addition, the reduced uniformity of crystal features may lead to dislocation or anomalous arrangement of crystals with irregular spacing, which automatically enhances the optical properties of such crystals.

Photoluminescent and photochromic smart window from recycled polyester reinforced with cellulose nanocrystals

“…To prepare rare‐earth‐doped aluminate phosphor nanoparticles, the solid‐state high‐temperature approach [ 32 ] was used, followed by the top‐down process. [ 33 ] Particle sizes were found to be in the 2–10 nm range as reported using a TEM ( Figure 1 ) .…”

“…A high‐temperature solid‐state technique was used to synthesize the strontium aluminate phosphor (SrAl 2 O 4 :Eu 2+ ,Dy 3+ ). [ 32 ] Strontium carbonate (0.2 mol; Merck), dysprosium oxide (0.01 mol; Aldrich), europium oxide (0.02 mol; Aldrich), aluminium oxide (2.0 mol; Aldrich), and boric acid (0.2 mol; Merck) were all dissolved in 250 ml of ethyl alcohol (100%), homogenized (25 kHz) for 1 h, exposed to air drying at 100°C for 20 h, and then ground for 3 h. The provided product was exposed to a 3‐h sintering process at 1300°C under a reductive carbon. To prepare the phosphor microparticles, we milled and sieved the supplied powder.…”

Preparation of afterglow and photochromic fibrous mats from polypropylene plastics to detect ultraviolet light

“…The size and form of REA particles were evaluated using a JEOL ing steps, a profile of the emission spectrum was reported. [4] The colour intensity (K/S) and Commission internationale de l'éclairage (CIE)…”

“…By repeating the foregoing steps, a profile of the emission spectrum was reported. [ 4 ] The colour intensity ( K/S ) and Commission internationale de l'éclairage (CIE) Laboratory parameters of the REANP‐dyed polypropylene fabrics were analyzed using an UltraScan PRO spectrophotometer (HunterLab, USA). [ 9 ] L*, b*, and a* represent the chromatic gamut from white (100) to black (0), from yellow (+b*) to blue (−b*), and from red (+a*) to green (−a*).…”

“…[ 2 ] Fluorescence is light emission that stops when the radiation source is switched off, whereas phosphorescence is afterglow light emission with durations from a fraction of second to 1 h after the radiation source is switched off. [ 3–5 ] For phosphorescence to endure for an extended time period, crystals and traps are the main components in phosphors. Light absorption is a defining feature of crystals, and the energy they release can be captured in traps.…”