摘要随着科学技术的发展,为了缩短新材料的开发周期,美国提出并实施了“材料基因组计划”。随着石墨烯等二文材料的优异性能被发现,对二文材料的挖掘成为研究热潮。过渡金属卤化物很多在自然界中储量丰富,其中很多种类具有层状结构。这类具有层状结构的过渡金属卤化物有希望制备成原子层二文材料,从而有机会同时拥有过渡金属原子强烈的电荷转移性质和二文材料独有的表面性质,可以应用在吸附和催化反应中。在本工作中,利用材料基因工程中的“计算平台”,通过基于密度泛函理论的第一性原理计算,对二文单层过渡金属卤化物进行结构驰豫和电学性质计算。结果显示,二文单层过渡金属卤化物拥有较广泛的电学性质,包含金属性和半导体,间接带隙和直接带隙。其中Ti、 V、 Cr等过渡金属卤化物带隙很小或为零, 有希望应用于锂电池材料; FeCl2、 VCl3、FeBr3拥有合适的直接带隙,在光致发光和场效应管等光电器件中有应用前景。 41651 毕业论文关键词 材料基因工程 二文材料 过渡金属卤化物 电学性质 密度泛函理论
Title Explore New Transition Metal Halides-Atomic Layer 2D Materials Based on Material Genome Engineering Methods
Abstract With the development of science and technology, in order to shorten the development cycle of new materials, the United States proposed and implemented the " Materials Genome Initiative(MGI)". When the excellent performance of graphene and other two-dimensional materials were found, a lot of research efforts have been made to find and investigate two-dimensional materials. Many transition-metal halides are abundant in nature, and many species have a layered structure. With layer structures promising synthesis of two-dimensional atomic layers of material, transition-metal halides have the opportunity to have both high charge transfer properties of transition-metal halides and unique properties of 2D materials, which can be used in adsorption and catalysis reaction. Through "computation platform" in the Materials Genome Initiative and first-principle calculations based on density functional theory, I did structure relaxation and electrical property calculations of two-dimensional single layer of transition-metal halides. The results show that these materials have broader electrical properties, including metal and semiconductor, indirect bandgap and direct bandgap. Ti, V and Cr halides’ bandgaps are very small or zero, promising applications in the Li+ batteries; FeCl2, VCl3 and FeBr3 have suitable direct band gaps which can applied to optoelectronic devices such as photoluminescence and FET.
Keywords Material Genome Engineering Two-dimensional materials Transition-metal halides Electrical properties Density functional theory
目次