Photoluminescence Properties and Stable Bipolar Resistive Switching Behavior of Two Eu(III)-Doped Hexameric Selenotungstates

Due to their structural versatility, selenotungstates have emerged as a prominent research focus in polyoxometalate (POT) chemistry. Two Eu(III)-doped hexameric selenotungstates with distinct architectures were synthesized via a one-pot synthetic strategy. Detailed structural investigations were prompted by their remarkable photoluminescence lifetimes of 759.8 μs (1) and 722.8 μs (2), significantly surpassing those of most reported Eu(III)-doped polyoxotungstates. Comparative analysis with literature precedents revealed a strong correlation between the luminescent behavior and the coordination environment of the Eu(III) centers. Furthermore, the compounds exhibited exceptional resistive switching performance at ambient conditions, with switching ratios of 1.03 × 10³ (1) and 3.67 × 10³ (2) that exceed most reported values for oligomeric POT-based systems. This work systematically investigates the structure-property relationships among molecular architectures, luminescent characteristics, and resistive switching behavior, providing experimental evidence for the design of new luminescent materials and molecular storage devices.