Photoluminescence/optical-absorption modulation of layered lanthanide molybdates for chemical sensing of reductive materials

Abstract

This work have found K1-δHδEu(MoO4)2 as a novel material for detecting reducing agents. The red emission from Eu3+ was notably diminished in the presence of the reducing agent, followed by its restoration in the presence of the oxidizing agent, demonstrating a significant luminescence modulation. This effect is believed to be induced by polaron absorption between Mo5+ and Mo6+, deactivating the red luminescence of Eu3+. Notably, the facile proton deinsertion stemming from the layered structure contributed to its exceptional restoration capability.

Acquisition of Emissive Single-Crystalline AEu(MoO4)2 (A = Na, K, Rb, and Cs) Double Molybdates by One-Pot Hydrothermal Synthesis: Relationship between Particle Morphology and Photoluminescence Properties

“…Precise control of the synthesis technique is crucial for improving the properties of these materials. Several liquid-phase syntheses, including coprecipitation, hydro/solvothermal, and sol–gel methods, have been developed to synthesize submicrocrystals and nanocrystals. − Due to its interesting structural and optical features, AEu­(MoO4)­2 has been extensively studied as a phosphor material. ,− ,,,,, Among these methods, hydrothermal synthesis stands out as one of the most effective “soft chemistry” techniques because it can proceed under mild conditions to obtain crystals. In contrast, coprecipitation and sol–gel methods often require high-temperature treatments to crystallize the particles.…”

Elucidation of the structural features and photoluminescence properties of a hydrothermally-synthesized γ-KEu(MoO4)2 microcrystal phosphor with metastable orthorhombic structure and differences in the luminescence properties by structure transition due to Y3+-dilution

“…Additionally, the chemical tunability stemming from the layered structure holds promise for further modifications and applications. 12,13…”

“…The α-KEu(MoO 4 ) 2 material has undergone extensive investigation regarding its detailed structure, luminescence properties, and chemical modifications through post-treatment methods, such as protonation and nano-scroll formation. 12,13 The simplicity of synthesis in the α-phase has facilitated these developmental studies. However, the SSR method employed for synthesis has limitations, particularly in controlling particle morphology and precisely tuning chemical compositions, including atomic defects.…”