Fabrication of highly flexible luminescent films, hydro gels and anti-counterfeiting applications of La2MoO6:Sm3+ phosphors

Abstract

Fabrication of versatile luminescent materials with remarkable quantum yield holds significant importance across various applications. In this context, a series of (1–11 mol %) Sm3+ activated La2MoO6 nanophosphors (LMO:Sm3+ NPs) has been developed. These nanophosphors, denoted as LMO:Sm3+ NPs, serve as a multifunctional platform with applications spanning white LED technology, flexible displays, hydro-gels, and anti-counterfeiting (AC) measures. These phosphors emit a vibrant orange-red light at 601 nm when excited at 402 nm owing to the Sm3+ ions 4G5/2 → 6H7/2 transition, achieving a high quantum yield of 66.2 %. The optimal doping concentration of Sm3+ ions in the LMO host material is identified as 5 mol %, with concentration quenching primarily attributed to electric multi-polar interaction. Remarkably, the newly fabricated LMO:Sm3+ phosphors exhibit a correlated color temperature (CCT) of 2064 K and maintain excellent color stability. Moreover, a transparent AC film is created using the optimized phosphor and Polydimethylsiloxane (PDMS), offering effective AC capabilities through their orange-red emission when exposed to 365 nm UV light. Notably, these phosphors exhibit sustainability, exceptional flexibility, and foldability, expanding their potential applications in the field of AC. These results underscore the potential of LMO:Sm3+ NPs as highly efficient luminescent platforms, catering to a wide range of applications, including white LED's, flexible display devices, hydro-gels, and AC solutions.