Ba ₃ ZnB ₅ PO ₁₄ as a Multifunctional Host for New Colored Compounds, White‐Light Emission, and Turn‐Off Luminescence Sensing

The deep‐UV nonlinear material, Ba 3 ZnB 5 PO 14 , has been explored for synthesizing new colored compounds, Tb 3+ /Tm 3+ ‐based white light emission and Eu 3+ ‐based turn‐off luminescence sensing. Isostructural analogues were obtained by partial substitution of Ba 2+ with Sr 2+ /Pb 2+ ions and V 5+ with P 5+ ions. Transition metal–substituted compounds display bright colors under daylight. The origin of color was understood based on ligand field transitions. The oxidation states of the transition metal ions were confirmed using x‐ray photoelectron spectroscopy (XPS) analysis. The near–IR reflectivity studies indicate that the synthesized compounds exhibit good near–IR reflectivity behavior. Rare‐earth substitution (Eu 3+ , Tb 3+ , Tm 3+ ) yield red, green, and blue emissions, respectively. White‐light emission was successfully achieved by optimizing the green (Tb 3+ ) and blue (Tm 3+ ) components. Based on the lifetime measurements, a possible schematic of the energy transfer pathway has also been proposed. Eu 3+ ‐substituted Ba 3 ZnB 5 PO 14 host was found to be sensitive and selective for the fluorometric detection of Pb 2+ , Fe 3 + , Cl − , and NO 2 − ions in aqueous medium with low detection limits. The dielectric studies indicate reasonable dielectric constant values with low dielectric loss. Magnetic studies indicate antiferromagnetic behavior. The different properties demonstrated in the present study suggests that mineral structures offer fertile ground to investigate newer compounds and properties.