Multifunctional POM-based inorganic-organic hybrids for proton conduction and selective sensing of Fe3+ ions
Year: 2025
Type: article
Abstract: Polyoxometalates (POMs), famous for their structural diversity and versatile properties, offer an attractive platform for constituting multifunctional materials through covalent assembly with lanthanide (Ln) ions, integrating optical, electrical, and magnetic functionalities. Herein, four three-dimensional (3D) POM-based inorganic-organic hybrids were successfully synthesized by hydrothermal method, [Ln4(HIDC)4(H2O)8(HBW12O40)]·2H2O (Ln = La (1), Ce (2); H3IDC = 4,5-imidazoledicarboxylic acid) and [Ln4(HIDC)4(H2O)6(HBW12O40)]·8H2O (Ln = Tm (3), Eu (4)). Among these hybrids, compound 4 emerges as a bifunctional material, exhibiting both proton conduction and fluorescence sensing capabilities. For proton conduction, compound 4 achieves a conductivity of 1.53 × 10‒5 S·cm‒1 at 65 °C and 95% relative humidity. To enhance conductivity and practical applicability, compound 4 was incorporated into a polyvinyl alcohol/glycerol (PVA/Gly) matrix, yielding the hydrogel Eu@PVA/Gly-15%. This hydrogel displays remarkable proton conductivity (1.01 × 10‒2 S·cm‒1 at 75 °C and ambient humidity) and flexibility, enabling the assembly of strain sensors with high sensitivity for detecting human joint movements. Simultaneously, compound 4 exhibits excellent aqueous stability and characteristic Eu3+ luminescence, facilitating selective detection of Fe3+ ions in aqueous media via fluorescence quenching. This work shows the versatility of POM-Ln hybrids in developing advanced materials for flexible electronics and chemical sensing.
Source: Journal of Molecular Science
Authors: Jingyi TENG, Guangqing WANG, Jingqi YANG, Shanshan LI, Ying LU
Institution: Northeast Normal University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W7128546644