层状磷酸铝化合物Na4[Al4P4O18]·H2O的合成及质子电导性能研究

在无有机模板剂的条件下, 以Na⁺离子为结构导向剂, 通过水热合成法制备了一种与利用1,3-丙二胺合成的Uio-14具有相同层结构的二维磷酸铝化合物Na₄[Al₄P₄O₁₈]·H₂O(1), 通过单晶X射线衍射确定了其拓扑结构. 利用粉末X射线衍射、 扫描电子显微镜、 电感耦合等离子体( ICP)元素分析和热重分析等对其物理化学性质进行了表征. 结果表明, 化合物1属于单斜晶系, 空间群为P2₁/c, 晶胞参数a=1.00887(9) nm, b=0.86747(8) nm, c=0.97580(9) nm, V=0.77387(12) nm³, Z=2, 其阴离子层由铝氧三角双锥(AlO₅)和磷氧四面体(PO₄)构成, 层间通过Na⁺离子平衡电荷; 与Uio-14相比, 化合物1具有更高的热稳定性, 在400 ℃空气条件下煅烧后结构仍然保持完好. 对化合物1的质子电导性能测试结果表明, 相比于传统的分子筛类材料, 化合物1展现出优异的质子电导性能, 在55 ℃下质子电导率可达到1.19×10^-3 S/cm.

Organotemplate-free Synthesis and Proton Conduction Properties of a Layered Aluminophosphate Na4[Al4P4O18]·H2O†

In the organotemplate-free system, a layered aluminophosphate Na₄[Al₄P₄O₁₈]·H₂O(1) was synthesized with Na⁺ ion as the structure-directing agent under hydrothermal condition. The structure was determined by single-crystal X-ray diffraction, and further characterized by powder X-ray diffraction(PXRD), scanning electron microscopy(SEM), inductively coupled plasma(ICP) and thermal gravimetric(TG) analyses. Compound 1 crystallizes in the monoclinic space group P2₁/c with a=1.00887(9) nm, b=0.86747(8) nm, c=0.97580(9) nm, V=0.77387(12) nm³, and Z=2, and its framework consists of AlO₅ and PO₄ units. Compound 1 possesses high thermal stability, and the crystal structure remains unchanged after calcination at 400 ℃ in air. The proton conductivity measurement gives that compound 1 possesses excellent conductivity with σ the value of 1.19×10^-3 S/cm when immersed in water at 55 ℃, which is higher than those of traditional zeolitic materials.