Development of a boron-doping strategy to activate luminescence in a non-emissive silver-incorporated polyoxoniobate

Silver-incorporated polyoxometalates (POM) exhibit significant application potential in optical devices, catalysis, and so on. However, the optical activities of such materials are often limited by weak argentophilic interactions within the structures or insufficient structural rigidity. In this study, a new non-emissive polyoxoniobate (PONb) containing discrete silver ions within the cluster skeleton, H₁₃K₆Na₁₃[(Te₄Nb₉O₃₆)₄Ag₆Te₂Nb₂O₆]·35H₂O, has been successfully synthesized and characterized. Interestingly, doping the light element boron during the synthesis activated the originally non-emissive PONb, inducing strong luminescence. Mechanistic investigations using electron energy loss spectroscopy and thermally perturbed two-dimensional infrared spectroscopy revealed that boron doping enhances structural rigidity, suppressing non-radiative decay pathways. This work not only presents a rare silver-incorporated PONb but also develops a promising strategy for activating non-emissive silver-incorporated POMs.