Facile production of smart superhydrophobic nanocomposite for wood coating towards long‐lasting glow‐in‐the‐dark photoluminescence

Abstract

A smart photoluminescent nanocomposite surface coating was prepared for simple industrial production of long‐persisting phosphorescence and superhydrophobic wood. The photoluminescent nanocomposite coatings were capable of continuing to emit light in the dark for prolonged time periods that could reach 1.5 h. Lanthanide‐doped aluminium strontium oxide (LASO) nanoparticles at different ratios were immobilized in polystyrene (PS) and developed as a nanocomposite coating for wood substrates. To produce transparency in the prepared nanocomposite coating, LASO was efficiently dispersed in the form of nanoscaled particles to ensure homogeneous dispersion without agglomeration in the PS matrix. The coated wood showed an absorption band at 374 nm and two emission bands at 434 nm and 518 nm. The luminescence spectra showed both long‐persisting phosphorescence as well as photochromic fluorescence relying on the LASO ratio. The improved superhydrophobicity and resistance to scratching of the coated wood could be attributed to the LASO NPs incorporated in the polystyrene matrix. Compared with the uncoated wood substrate, the coated LASO‐PS nanocomposite film also displayed photostability and high durability. The current study demonstrated the potential high‐scale manufacturing of smart wood for some applications such as safety directional signs in buildings, household products, and smart windows.

Colour‐switchable and photoluminescent polyvinyl chloride for multifunctional smart applications

“…As the UV irradiation time was increased from 50 to 400 s, the emission intensities in the blue and green bands shifted from 429 to 513 nm, respectively. The Eu 2+ 4 f –5 d transition demonstrated green (513 nm) and blue (429 nm) emission bands [ 12,29 ] Two Sr sites were accountable for these emission bands. It is possible that thermal quenching under ambient conditions would lower the blue colour's brightness to almost nothing.…”

“…The 4f 6 5D 1 ↔4f 7 transition of Eu 2+ ions has been linked to the emission of LaAN. [ 12,29 ] A complete Eu 3+ to Eu 2+ exchange was established because Dy 3+ or Eu 3+ emission peaks were missing from the luminescence. Dy 3+ light traps can cause Eu 2+ to return to its ground state in the dark.…”

“…Smart materials are those that respond to external stimuli such as heat and light in a manner that can be controlled and reversed. [ 9–15 ] As a result of their responsiveness capability to hazardous environmental stimuli, such as elevated temperature and poisonous compounds, smart substances have been utilized in the creation of protective merchandise. An irradiation source is necessary to trigger the emission of a specific substance, and the material's emission recovers as soon as the supply is removed to indicate fluorescence emission.…”

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

“…As a result of these liberated holes, Eu(II) reverts to ground state, resulting in light emission. [ 60–62 ] Photoluminescent materials must be able to withstand repeated cycles of colouration and decolouration, which may lead to fatigue. As a result, following exposure to UV light, the emission spectra were used to record reversibility and photostability.…”

Synthesis of lanthanide‐doped strontium aluminate nanoparticles encapsulated in polyacrylonitrile nanofibres: photoluminescence properties for anticounterfeiting applications

“…[20] The rare-earth-doped strontium aluminium oxide phosphor is one of the best rare-earth-doped phosphors due to its distinct properties, such as nontoxicity, thermal and photostability, brightness, long-lasting time (>10 h), nonradioactivity, resistant capability to chemicals and recyclability. [21][22][23][24][25] Therefore, the fabrication of UV-stimulated photochromic LSAN-immobilized PAN nanofibrous films is an attractive innovative practice for anticounterfeiting materials with photostability, high durability, low cost, and superhydrophobicity. These characteristics open new horizons to build up more efficient and stable anticounterfeiting materials.…”