Utilization of Aloe vera-infused Sm3+ doped La2MoO6 nanophosphors: Their role in anti-counterfeiting, white LEDs and transport properties

Abstract

In the realm of anti-counterfeiting (AC) measures, the focus has increasingly turned towards fluorescent inks, appreciated for their practicality and environmentally friendly nature. However, their susceptibility to wear and vulnerability to moisture damage has hindered their widespread application. Additionally, most available fluorescent inks are single-colored, toxic, and skin-irritating, making them ill-suited for real-world use. In light of these challenges, this article delves into the impact of introducing Sm3+ ions into the La2MoO6 host lattice. The green solution combustion method is employed to synthesis 1–11 mol % Sm3+ doped La2MoO6:Sm3+ nanophosphors (LMO:Sm3+ (1–11 mol %) NPs. The effects of rare earth doping are examined through X-ray diffraction, scanning electron microscopy-energy dispersive spectroscopy, and photoluminescence (PL) analysis. The PL spectra reveal four emission bands, with a prominent 603 nm wavelength band emitting an orange-red hue attributed to the electronic transition of Sm3+ ions. Notably, the impact of Sm3+ ion doping on the phosphor’s luminescence spectra is prominently featured. The optimal concentration is found to be 5 mol % (LMO:5Sm3+), with concentration quenching primarily attributed to exchange-type interactions. The luminescent properties are evidenced by Commission Internationale de l’éclairage (CIE) color coordinates (0.6063, 0.3901), color purity (CP = 99.10 %), and correlated color temperature (CCT = 1383 K). Furthermore, the study delves into optical parameters such as energy band gap and refractive index, revealing values of 2.313 and 2.252 eV, respectively, for the optimal molar concentration. These findings hold promise in the development of AC inks suitable for screen-printing and writing on a variety of surfaces. The resultant patterns exhibit vivid orange-red fluorescence under UV 365 nm irradiation, showcasing potential applications in encryption, security marking, and optical authentication.