Simple Preparation of Photoluminescent and Color-Tunable Polyester Resin Blended with Alkaline-Earth-Activated Aluminate Nanoparticles

Abstract

A simple inorganic/organic nanocomposite was used to generate long-lasting phosphorescent pebbles for easy commercial manufacturing of smart products. An organic/inorganic nanocomposite was made from low-molecular-weight unsaturated polyester and rare-earth-activated strontium aluminum oxide nanoparticles doped with europium and dysprosium. The polyester resin was mixed with phosphorescent strontium aluminate oxide nanoparticles and methylethyl ketone peroxide as a cross-linking agent to create a viscous mixture that can be hardened in a few minutes at room temperature. Before adding the hardener catalyst, the phosphorescent strontium aluminate nanoparticles were dispersed throughout the polyester resin in a homogeneous manner to ensure that the pigment did not accumulate. Long-lasting, reversible luminescence was shown by the photoluminescent substrates. The emission was reported at 515 nm upon exciting the pebble at 365 nm. In normal visible light, both blank and luminescent pebbles had a translucent appearance. As a result of UV irradiation, the photoluminescent pebbles produced an intense green color. The three-dimensional CIE Lab (International Commission on Illumination) color coordinates and luminescence spectra were used to investigate the color changing characteristics. Photophysical characteristics, including excitation, emission, and lifetime, were also investigated. Scanning electron microscopy, wavelength-dispersive X-ray fluorescence spectroscopy, and energy-dispersive X-ray analysis were employed to report the surface morphologies and elemental content. Without impairing the pebbles’ original physico-mechanical characteristics, the pebbles showed improved superhydrophobic activity. The current simple colorless long-lasting phosphorescent nanocomposite can be applied to a variety of surfaces, like ceramics, glassware, tiles, and metals.

Optical properties of novel luminescent nacre‐like epoxy/graphene nanocomposite coating integrated with lanthanide‐activated aluminate nanoparticles

“…The detection limit of XRF has been typically reported at 10 ppm. [ 35 ] Therefore, partial determination of the nacre‐like chemical composition was reported by XRF (Table 2). Accordingly, Sr and Al were identified by XRF in all luminous nacre‐like coatings.…”

“…Both Commission Internationale de L'éclairage (CIE) Laboratory and colour strength ( K/S ) parameters were analyzed. [ 35 ] The CIE Laboratory represents colour as 3D numerical coordinates; where L* is brightness from black(0) to white(100), a* is the range of colours from red (+a*) to green (−a*), and b* is the range of colours from yellow (+b*) to blue (−b*). Before and after illumination with UV light, photographs of luminescent nacre‐like coats were captured using a Canon A710IS instrument.…”

Simple preparation of novel photochromic polyvinyl alcohol/carboxymethyl cellulose security barcode incorporated with lanthanide‐doped aluminate for anticounterfeiting applications

“…The photoluminescent films displayed virtually similar emission characteristics to those with the LdA powder. [ 44,59 ]…”

“…The 4f 6 5D 1 ↔4f 7 transition of europium (II) ions was responsible for the fluorescence of LdA. [ 57–59 ] Neither europium (III) nor dysprosium (III) showed any typical fluorescence peaks to demonstrate a full conversion of Eu(III) into Eu(II). This indicated that dysprosium (III) absorbed light that then transferred to Eu(II).…”

“…The photoluminescent films displayed virtually similar emission characteristics to those with the LdA powder. [44,59] Using a UV light source, all samples showed reversible photoluminescence. Those with LdA at a concentration of less than 0.6%…”