【摘要】 为了探讨化学成份对VPO体系孔道结构化合物结构稳定性的影响,根据酸碱平衡原理进行了合成实验设计;利用V2O5、H3PO4、H3BO3 等简单的无机前驱物、乙二胺作结构导向剂,水热法合成了孔道结构钒硼磷酸盐化合物(H3NCH2CH2NH3 )2 (H3NCH2CH2NH2 ) [VⅢ (H2O)2 (VⅣO)8 (OH)4 (H(P,B)O4 )4 ( (P,B)O4 )4 (H2O)2 ]·3H2O(简称V9 (P,B)8 en)。典型的反应起始物摩尔比为n(V2O5 ):n(H3BO3 ):n(H3PO4 ):n(en):n(H2O) =0. 89:3. 50: 3. 50: 3. 60: 265(pH值为 6. 5),在 175℃、自生压力条件下恒温晶化 6. 5d(最终pH值为 5. 9 )。通过电子探针、粉末X射线衍射、红外吸收光谱、原子占位度修正等方法,对产物的化学成份、物相及其结构等进行了实验研究。证实V9 (P,B)8 en为V9P8 en的类质同象化合物,不同晶粒中B与P的含量有差别,B与P之比为 0. 1: 7. 9~2. 54: 5. 46(原子比),但恒有V: (P+B)≈9: 8。表明通过合理设计和控制合成条件,可在保持V9P8 en基本结构不变的前提下通过同晶取代引入新的化学成份,并由此探讨成份与结构稳定性的关系。更多还原

【Abstract】 For the purpose of probing into the influence of chemical component on the framework stability of VPO system, a synthetic strategy was presented and a series of hydrothermal synthesis experiments were designed rationally based on the valence-matching principle. One vanadium borophosphate,（H₃NCH₂CH₂NH₃）₂（H₃NCH₂CH₂NH₂）[V^Ⅲ（H₂O）₂（V^ⅣO）₈（OH）₄ （H（P,B）O₄）₄（（P,B）O₄）₄（H₂O）₂]·3H₂O（V₉（P,B）₈-en for short）, was synthesized hydrothermally by molecular self-assembly technique. The typical molar ratio of starting reagents was n（V₂O₅）:n（H₃BO₃）:n（H₃PO₄）:n（en）:n（H₂O）= 0.89:3.50:3.50:3.6:265, and the hydrothermal reaction was run in 50 mL Teflon-lined stainless-steel autoclave（filling volume of 45～50%） at 175℃ for 6.5 days under autogenous pressure. The starting and the final pH values were 6.5 and 5.9 respectively. By EPMA, FT-IR and XRD methods, the chemical component and crystal structure of the compound were determined. It was shown that the atomic ratio of P:B was variable from 0.1:7.9 to 2.54:5.46 in different crystals, but the atomic ratio of V:（P+B） was almost 9:8 constantly. This blue tabular compound V₉（P,B）₈-en was an allomer of V₉P₈-en. By refining the site occupancy of V and P atoms in the structure of one crystal investigated, it was demonstrated that element B substituted partially for P in tetrahedron, and the atomic ratio of B:P was 0.1838:7.8162. The successful syntheses of this compound should be helpful for the investigation of the structural stability mechanism of open framework vanadium phosphates.更多还原