PVP-functionalized DyO/PrO nanocomposites: a multifunctional platform for photoluminescence, WLEDs, latent fingerprinting, and anti-counterfeiting applications.

Luminescent nanomaterials that combine high optical performance with multifunctional utility are essential for next-generation optoelectronic and forensic applications. However, achieving simultaneous enhancement of photoluminescence efficiency and practical applicability remains a challenge. Here, we report the synthesis of PVP-functionalized DyO/PrO nanocomposites a solution combustion route, where surface passivation with 9 wt% polyvinylpyrrolidone (PVP) effectively reduced crystallite size and improved dispersion. Structural and spectroscopic analyses confirmed strong polymer-oxide interactions, leading to defect passivation and enhanced luminescence. Photoluminescence studies demonstrated intense Dy-Pr emissions with a prolonged decay lifetime (5.2 ns) and a high quantum yield (92.16%). Chromaticity analysis indicated warm white light emission (CCT ≈ 5826 K, CRI ≈ 92), underscoring their suitability for high-quality WLEDs. Beyond lighting, the nanocomposites enabled clear visualization of latent fingerprints under UV illumination, revealing level 1-3 ridge details, and served as a covert UV-responsive ink for anti-counterfeiting applications. These results position PVP-coated DyO/PrO nanocomposites as a versatile platform bridging solid-state lighting, forensics, and security technologies.