Proton-Conducting 3D Polyoxoniobate Supramolecular Frameworks via Exclusive Guanidinium and Synergistic 4p–4f Metal-Oxo Clusters
A strategy focusing on framework stability and proton-conducting hydrogen-bonding networks in polyoxoniobates (PONbs) has been implemented, wherein protonated organic amines act as exclusive counter cations, synergistically enhanced by embedded 4p-4f metal-oxo clusters. This approach yields a new family of three-dimensional (3D) supramolecular frameworks, H<sub>6</sub>(CN<sub>3</sub>H<sub>6</sub>)<sub>8</sub>[As<sub>4</sub>Ln<sub>4</sub>O<sub>12</sub>(H<sub>2</sub>O)<sub>4</sub>(CO<sub>3</sub>)<sub>4</sub>(Nb<sub>5</sub>O<sub>14</sub>)<sub>2</sub>]·34H<sub>2</sub>O (<b>1-Ln</b>, Ln = Sm, Eu, Tb, Dy, Ho, Er, Yb), representing the first reported PONbs featuring a "double-tetrahedral, coaxially nested" 4p-4f metal-oxo cluster (As<sub>4</sub>Ln<sub>4</sub>). Impedance measurements show that <b>1-Eu</b> exhibits a proton conductivity of 1.21 × 10<sup>-2</sup> S·cm<sup>-1</sup> at 85 °C and 98% RH. Water vapor adsorption reaches saturation at <i>P</i>/<i>P</i><sub>0</sub> = 0.946 with a maximum uptake of 296.6 cm<sup>3</sup>·g<sup>-1</sup>. In addition, <b>1-Eu</b> and <b>1-Tb</b> display characteristic lanthanide-centered luminescence.
Authors
- S. Lilly Zheng (ORCID: https://orcid.org/0009-0005-2271-9299)
- Yu‐Diao Lin
- Xin-Xiong Li
- Wen-Xu Zheng
- Run-Qing Wen
Institutions
- Fujian Normal University (CN)
- Fujian Provincial Hospital (CN)
- Fuzhou University (CN)
Publication Details
- Journal
- Inorganic Chemistry
- Published
- 2026-02-25
- DOI
- https://doi.org/10.1021/acs.inorgchem.6c00291
- Primary Topic
- Polyoxometalates: Synthesis and Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.00