In this work, a novel organodiphosphate-containing inorganic–organic hybrid polyoxoniobate (PONb) ring {(PO₃CH₂CH₂PO₃H)₄Nb₈O₁₆}^4– (Nb₈P₈) has been achieved by a one-pot hydrothermal method. The ring is constructed from a tetragonal {Nb₈O₃₆} motif and four {PO₃CH₂CH₂PO₃H} ligands. Interestingly, Nb₈P₈ can be joined together via K–H₂O clusters {K₂(H₂O)₄(OH)₂} to form one-dimensional chains {[K₂(H₂O)₄(OH)₂]Nb₈P₈}_n and further linked by {Cu(en)₂}²⁺ (en = ethylenediamine) complexes, resulting in a three-dimensional supramolecular framework {[Cu(en)₂]₂[K₂(H₂O)₄(OH)₂]Nb₈P₈}·3en·H₂O (1). 1 exhibits good chemical and thermal stability and has a high water vapor adsorption capacity of ≤224 cm³ g^–1 (22.71 mol·mol^–1) at 298 K, outperforming most of the known polyoxometalate-based materials. Impedance measurements prove that 1 can transfer protons with moderate conductivity. This study not only contributes to the structural diversity of organodiphosphate-containing PONbs and PONb rings but also provides a reference for the development of PONb-based materials with unique performance.

中文翻译：

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含有机二磷酸酯的多铌酸环及其通过氢键组装成三维骨架


在这项工作中，一种新型的含有机二磷酸盐的无机-有机杂化聚氧铌酸酯（PONb）环{(PO ₃ CH ₂ CH ₂ PO ₃ Nb ₈ O ₁₆ } ^4– (Nb ₈ P ₈ O ₃₆ } 基序和四个 {PO ₃ CH ₂ CH ₂ H} 配体。有趣的是，Nb ₈ P ₈ 可以通过 K–H ₂ O 簇 {K ₂ (H ₂ (OH) ₂ } 形成一维链 {[K ₂ (H ₂ O) ₄ (OH) ₂ ]Nb ₈ P ₈ } _n 进一步通过 {Cu(en ) ₂ } ²⁺ (en = 乙二胺) 配合物，形成三维超分子框架 {[Cu(en) ₂ ] ₂ (H ₂ O) ₄ (OH) ₂ ]Nb ₈ P < b39> }·3en·H ₂ O (1)。 1表现出良好的化学和热稳定性，在298 K时具有≤224 cm ³ g ^–1 (22.71 mol·mol ^–1 )的高水蒸气吸附能力，优于大多数已知的多金属氧酸盐基材料。阻抗测量证明1可以以中等电导率传输质子。该研究不仅有助于实现含有机二磷酸酯的PONb和PONb环的结构多样性，而且为开发具有独特性能的PONb基材料提供参考。