Syntheses And Characterizations Of Open-framework Ti-containirig Phosphites/Phosphates And Silicogermanates

Inorganic open-framework compounds, typically known as zeolites, haveregular porosity, rich chemical composition and abundant structural diversity.Nowadays, the applications of inorganic open-framework materials are not onlyconfined in the fields of catalysis, gas adsorption and separation, but also widelyextend to non-linear optical materials, semiconductor materials and microreactors.Open-framework aluminophosphates and germanosilicates as two main families ofopen-framework materials have attracted more attentions due to their uniquestructures and wide applications.This thesis focuses on the study of Ti-doped aluminophosphate andgermanosilicate open-framework compounds by using the hydrothermal andionothermal synthetic routes. Main results are as the followings:1、 The first open-framework titanium phosphite TiHPO-CJ1has beensynthesized under hydrothermal and ionothermal conditions. TiHPO-CJ1exhibitsnovel three-dimensional (3D) open-framework structure, which is constructed byalternate connection of six coordinated TiO6and pseudo tetrahedra HPO3. Theframework contains8-ring channels along the [100] direction, and the aperture isabout3.86×2.53(O···O distance). The introduction of Ti in the frameworkendows the compound TiHPO-CJ1with photoelectric activity. When illuminatedwithout external electric field, an SPV response in the range of300-370nm (max.335nm) is observed for TIHPO-CJ1. Field-induced surface photovoltagespectroscopy (FISPS) study shows that the intensity of the SPV response decreaseswith the enhanced positive electric-field strength. Photovoltaic properties ofTIHPO-CJ1enrich functional inorganic crystal materials and allow us to exploremore new inorganic photovoltaic material.2、 By using2-Methyl-1,5-diaminopentane as template, an open-frameworkTi-doped aluminophosphate TiAPO-CJ2and a silicogermanate molecular sieveSiGeO-CJ3with NON-type structure have been synthesized under hydrothermalconditions. The influence of various synthetic variables, such as crystallization time, and the contents of acid, template, mineralizing agent and water, etc. on theformation of these two compounds have been discussed in detail. The structures ofthese two compounds have been preliminary charactered. Further study of theirstructures and properties needs further investigation.