【作者】 王丽丽；

【导师】 赵纪军；

【作者基本信息】 大连理工大学 ， 凝聚态物理， 2011， 硕士

【摘要】 近年来,对纳米多孔材料如金属有机骨架化合物(MOF)和共价有机骨架化合物(COF)的研究成为了各国科研工作者关注的热点。这两种材料具有可设计的结构、可调控的孔隙以及高的热稳定性等诸多优点,被广泛应用在储气、分离、催化、及制药等领域。另外,氧化石墨烯材料作为石墨烯材料的一种衍生材料,其用途也是十分广泛的。由于石墨烯材料上存在大量的含氧基团,因此过渡金属原子可以很容易的担载在其表面,而使氧化石墨烯的性质发生一定的改变。本文采用第一性原理和巨正则蒙特卡罗模拟两种方法,研究了MOF和COF材料对有害气体的吸附属性,以及改性后的氧化石墨烯材料对CO气体分子的捕捉和分离特性,主要研究内容如下：1、通过巨正则蒙特卡罗方法研究了几种典型的骨架化合物(COF-105, COF-108, MOF-5和MOF-177)在298 K时,对CO, NO和NO2的吸附能力。结果表明这四种材料对NO2的吸附量都比较高,尤其是MOF-177,在温度和压强分别为298 K和10 bar时,对N02的吸附量可以达到10.7 mmol/g。根据模拟的吸附热结果,我们进一步讨论了四种气体(H2, CO, NO和NO2)和四种吸附剂材料(COF-105, COF-108, MOF-5和MOF-177)的相互作用。2、通过第一性原理和巨正则蒙特卡罗方法,研究了担载Ti的氧化石墨烯材料对CO的吸附和分离属性,结果表明在温度和压强分别为298 K和10 bar时,CO的吸附量可以达到7.5 mmol/g,是模拟的其它气体(CO2,N2和CH4)吸附量的2到6倍。因此担载Ti的氧化石墨烯可以作为良好的CO分离材料。所以我们也可以通过担载不同的原子来研究不同金属修饰的氧化石墨烯材料对其它气体的分离能力。更多还原

【Abstract】 In recent years, the study of nanoporous materials such as metal organic framework and covalent organic framework, become a hot topic of researchers. Due to the excellent characteristics of the two materials such as large surface areas, adjustable pore sizes and controllable properties, as well as acceptable thermal stability, they are widely applied in gas storage, separation, catalyst and pharmacy, etc. Moreover, as a derivative product of graphene, graphene oxide (GO) has attracted resurgent interests. Owing to large amounts of oxygen groups on GO surface, transition metal atoms can be easily supported on the surface, and improve the capacity of GO.In this work, the first-principles computations and Grand Canonical Monte Carlo (GCMC) were performed to investigate the adsorption behaviors of nanoporous materials (MOFs and COFs) and the adsorption/separation capacities of CO in metal supported GO. The main contents are summarized as follows.1. The adsorption properties of CO, NO, and NO2 in several typical nanoporous materials (COF-105, COF-108, MOF-5 and MOF-177) at 298 K were investigated by Grand Canonical Monte Carlo (GCMC) simulations. The adsorption amounts of NO2 in these materials are higher than those of the other three gases because of the stronger gas-sorbent interaction. In particular, NOt adsorption amount in MOF-177 can reach as high as 10.7 mmol/g at 298 K and 10 bar. The interaction between the four gases (H2, CO, NO and NO2) and the COF/MOF adsorbents is further discussed in terms of the isosteric heat.2. The adsorption properties of selected gases (CO, N2, CO2 and CH4) on the Ti-decorated GO surface have been systematically studied by first-principles calculations and GCMC simulations. GCMC simulations of adsorption isotherms further demonstrate that the adsorption amount of CO can reach as high as 7.5 mmol/g at 10 bar and room temperature, the adsorption amount of CO is 2-6 times of the other gases (CO2, N2 and CH4). So the results show that the Ti-decorated GO materials can be ideal sorbents for CO capture and separation from mixtures with N2, CO2, and CH4. In addition to Ti, GO-based materials with other metal decoration may find potential applications for capture and separation of other gases.更多还原