In Situ Ligand-Transformation-Assisted Assembly of a Polyoxometalate and Silver-Phosphine Oxide Cluster for Colorimetric Detection of Phenol Contaminants.

In situ ligand transformation strategies represent an efficient pathway for constructing function-oriented polyoxometalate (POM)-based crystalline materials. Herein, three POM-based hybrid networks were synthesized through in situ transformation of the phosphine ligand, formulated as [Ag(dppeo)][HPMoO]·5HO (), [Ag(dedpo)][SiWO]·6HO (), and [Ag(dppeo)][PWO]·3HO () (dedpo = (2-(diphenylphosphaneyl)ethyl)diphenylphosphine oxide; dppeo = ethane-1,2-diylbis(diphenylphosphine oxide)). During the synthesis of these compounds, the 1,2-diphenylphosphine ethane molecule underwent in situ oxidation, transforming into dppeo and dedpo ligands, respectively. Compound features a supramolecular architecture assembled from [Ag(dppeo)]/[Ag(dppeo)] cationic clusters with disordered Ag centers and protonated [HPMoO] anions. Compound presents a 3-D POM-supported metal-organic framework consisting of binuclear [Ag(dedpo)] units, {-dedpo-Ag-dedpo-} chains, and [SiWO] polyoxoanions. Compound displays a 2-D layered structure formed by {-dppeo-Ag-dppeo-} chains and [PWO] clusters. Pronounced argentophilic interactions are observed in compounds and . The three compounds demonstrate satisfactory heterogeneous catalytic activity in the colorimetric detection reactions toward phenol pollutants with detection limits of 1.73, 1.92, and 4.6 μM, respectively. Additionally, compounds - show high anti-interference capabilities and high sensitivity in differentiating phenol from its halogenated derivatives. This work presents some guidance for designing specific function-oriented POM-based materials via an in situ ligand transformation strategy.