Various Applications of Gadolinium Molybdate Down‐Conversion and Up‐Conversion Fluorescent Nanoparticles

Crystalline α‐Gd 2 (MoO 4 ) 3 is synthesized by sintering at 800 °C using a coprecipitation method to prepare the precursor. The resulting α‐Gd 2 (MoO 4 ) 3 displayed a monocrystalline structure with a strong main peak (‐221) in the X‐ray diffraction signal. To develop a light‐emitting material, rare earth ions are added during synthesis. By doping with Tb 3+ and Eu 3+ , the Gd 2 (MoO 4 ) 3 down‐conversion phosphor shows potential for use in UV–LED chips, counterfeit money prevention, and fingerprint identification. Additionally, co‐doping with [Er 3+ ]/[Yb 3+ ] and [Ho 3+ ]/[Yb 3+ ] ions produce green and red emissions when applied to a 980 nm LED chip, useful for anti‐counterfeit ink. The magnetic properties of gadolinium are leveraged to confirm magnetic resonance imaging luminescence. A flexible composite for heat detection and explored various applications for its use is also developed.