【作者】 张新涛；

【导师】 杨明莉；

【作者基本信息】 重庆大学 ， 应用化学， 2007， 硕士

【摘要】 酶模拟催化体系一直是科学家研究的热点,按照生物化学、分子生物学、无机生物学、聚合物化学、配位化学、计算机模拟化学的基本原理,一些催化特性的人工酶已经被设计出来了。论文就近几年出现的一种新的酶模拟体系-金属有机络合聚合物(MOCPs)就其合成表征以及催化特性进行研究。MOCP作为一种新颖的酶模拟体系,在催化方面展示出一种诱人前景。由于目前这一领域的工作者研究的焦点主要集中在MOCP合成上,很少研究其催化特性,对模拟酶这个概念还未涉及。至于MOCP的合成方法,目前主要集中在高压高温反应釜中水热合成法,由于其反应时间长,且产率太低,因此在实际中研究其在合适温度下合成MOCP是非常重要的。论文应用低温水热合成法,用三种不同的多齿羧酸配体和Cd(Ⅱ)配位合成MOCP,结果发现合成出了三种不同结构的MOCP晶体。在实验和理论上研究分析了构建分子浓度、pH值、NH3·H2O用量、温度及降温速率对晶体形成影响规律。用红外光谱法确认了骨架中的有机官能团;用粉末和单晶的X射线衍射分析法测定了MOCP的晶体结构,并确定其骨架的组成;通过低温氮气吸附等温线测定了其比表面积和孔径分布;以热重分析(TGA)和差热分析(DTA)测定材料骨架的热稳定性。此外,还测定了晶体的溶解性能,并筛选了其中一种晶体对其进行光催化特性探索。研究发现,MOCP能在低于100℃氨水作为溶剂的水热反应条件下大约8个小时左右被合成出来,同时我们通过大量实验发现了控制晶体合成的规律。合成的MOCP能作为一种耐热,耐酸碱,以及部分溶剂的良好材料。其中经过活化的MOCP(镉离子与异烟酸合成的)具有光催化特性是一种半导体催化剂,经过修饰有望成为一种废水处理的催化剂。更多还原

【Abstract】 Mimic enzyme systems are always hotspots scientists study. Some artificial enzymes with different catalytic properties have been designed based on the elementary principles of biochemistry, molecule biology, inorganic chemistry, polymer chemistry, and computer chemistry. In this paper, approaches to synthesis, characterization and investigation of catalytic property are investigated for a class of promising functional porous materials arising recently, catalytic Metal-Organic Coordination Polymers (cMOCPs).As a novel enzyme mimic systems, cMOCPs display an attractive potential in catalysis. Currently, most workers focus on the MOCPs synthesis, but know little about their catalytic properties, and have not mentioned to the concept of cMOCPs mimic enzyme. As for the synthesis methods, most people use hydrothermal synthesis in Teflon-lined autoclave. But it is low in output and usually takes a long period time. So it is very important in practice to synthesize cMOCPs in milder conditions.In the paper, three different multidentate carboxylic acid ligands were used to combined with as Cd(Ⅱ), respectively, resulting in three MOCPs single crystals with different structures with a low temperature hydrothermal synthesis method. The effects of concentration of building molecules, pH values, ammonia usage, temperature and coolimg rates on crystal formation were studied experimentally and explored theoretically. The samples were characterized with IR spectra to affirm the organic groups in the frameworks, single-crystal X-ray diffraction to determine the crystal structure and composition of frameworks, N2 adsorption isotherms at low temperature to measure the specific surface area and pore size distribution, and with TGA/DGA analysis to scale the thermal stability. Furthermore, dissolution properties and the catalytic property of MOCP were explored.We found that above MOCPs single crystals could be hydro-thermally synthesized in an ammonia solution at no more than 100℃for eight hours. And at the same time we experimentally discovered some synthesis rules controlling crystal formation. The synthesized MOCPs are stable in heat, acid, alkali and commonly used solvents. Even one of MOCPs after being activated became a semiconductor photo-catalyst, which could be used to treat polluted water.更多还原