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

Abstract

Nacre structure has aragonite polygonal tablets, tessellated to generate separate layers, and exhibits adjacent layers and tablets within a layer bonded by a biopolymer. Here, we report the development of a nacre‐like organic/inorganic hybrid nanocomposite coating consisting of epoxy tablets as well as rare‐earth‐activated aluminate and graphene oxide tablet/tablet interfaces. The lanthanide‐activated aluminate was prepared using a high temperature solid‐state approach followed by top‐down technology to provide the phosphor nanoparticles (PNPs). Graphene oxide nanosheets were prepared from graphite. The prepared epoxy/graphene/phosphor nanocomposites were applied onto mild steel. Covalent bonds were formed between epoxy polymer chains resin and the graphene oxide nanosheets. These interface interactions resulted in a tough surface, high tensile strength, and excellent durability. The use of phosphor in the nanoparticle form guaranteed that no agglomerations were produced throughout the hardening procedure by allowing better distribution of PNPs in the nacre‐like matrix. The generated nacre‐like substrates displayed reversible fluorescence. The excitation of the white coloured nacre‐like coats at 367 nm resulted in a green emission band at 518 nm as designated by the Commission Internationale de l'éclairage (CIE) Laboratory and photoluminescence spectra. Various analysis methods were utilized to inspect the surface structure and elemental composition of the nacre‐like coats. An improved hydrophobicity and mechanical characteristics were detected when increasing the phosphor concentration. Due to the astonishing characteristics of the prepared nacre‐like composite paint, both ceramics and metals can benefit from the current simple strategy.

Dual mode stimuli‐responsive color‐tunable transparent photoluminescent anticounterfeiting polycarbonate electrospun nanofibers embedded with lanthanide‐doped aluminate

“…The RESAO@PC films exhibited transparent backgrounds, which aided in the detection of the ultraviolet‐induced color change to green emission 29–32 . After being exposed to ultraviolet light, all RESAO@PC nanofibers exhibited an instantaneous and reversible photochromism.…”

“…The RESAO@PC films exhibited transparent backgrounds, which aided in the detection of the ultravioletinduced color change to green emission. [29][30][31][32] After being exposed to ultraviolet light, all RESAO@PC nanofibers exhibited an instantaneous and reversible photochromism. Nonetheless, the RESAO@PC samples with RESAO ratio below 0.9% showed fluorescence with quick reversibility after switching off the UV source.…”

“…On the other hand, a phosphorescent substance continues to emit light after turning the excitation light source off. This phosphorescent light emission continues for seconds (phosphorescence) or even hours (afterglow) 30–32 . Numerous photoluminescence uses, such as warning signs, make extensive use of rare‐earth doped phosphors.…”

“…This phosphorescent light emission continues for seconds (phosphorescence) or even hours (afterglow). [30][31][32] Numerous photoluminescence uses, such as warning signs, make extensive use of rare-earth doped phosphors. Numerous rare-earth doped phosphors with varying primary colorimetric emissions have been described in the literature, such as CaAl 2 O 4 :Eu 2+ , Nd 3+ as bluish emitters, 33 CaS:Eu 2+ , Tm 3+ , Ce 3+ as red emitters, 34 and SrAl 2 O 4 :Eu 2+ , Dy 3+ as greenish emitters.…”

Synthesis and molecular docking of novel fluorescent alkoxy‐substituted iodobiphenyl analogues

“…Photoresponsive compounds can change their physical and/or chemical features upon exposure to light [22][23][24][25][26][27][28][29][30][31][32][33]. Here, different organic solvents were used to examine both the absorbance and fluorescence activities of the synthesized iodobiphenyl ethers, as summarized in Table 1.…”