基于3d元素掺杂的石墨二炔分子传感材料性能调控

二维碳材料因其独特的性质成为凝聚态物理、纳米电子学、生物医药等领域的前沿研究热点。石墨二炔具有天然的半导体特性及独特的大孔网状结构,在纳米电子器件和生物传感方面比石墨烯更具优势。本文使用第一性原理计算研究了单层石墨二炔的纳米带电子输运性质和及石墨二炔对小分子的吸附。我们考虑用掺杂3d金属原子的方法来增强对分子的吸附力。选择在石墨二炔表面吸附能较大的钪(Sc)、钛(Ti)原子,确定石墨二炔表面Sc、Ti单原子在室温下的稳定性,研究了Sc、Ti掺杂石墨二炔用于分子检测的潜在可能。从能带、载流子浓度等方面全面探讨了Sc、Ti掺杂石墨二炔对甲醛分子(HCHO)的响应。又进一步研究了石墨二炔与氨基酸分子间相互作用,发现色散力在相互作用中占主导地位。研究了吸附氨基酸对石墨二炔电子输运的影响,探讨石墨二炔在生物传感方面的潜在应用。

Modulation of Molecular Sensing Properties of Graphdiyne Based on 3d Impurities

In recent years, the successful preparation of single-layer graphene, MoS₂, and other two-dimensional materials has started a new era of two-dimensional materials.The potential applications of two-dimensional materials in emerging electronics have drawn widespread attention.Two-dimensional carbon materials, with their unique properties, have become the research hotspot of condensed matter physics, nanoelectronics, and biological medicine.The remarkable success in preparing graphene provides additional possibilities for developing sensitive biodevices and medicine systems.However, graphene is gapless and thus is unsuitable for building nanoelectronic devices or biosensors due to the too low on/off current ratio.More than 20 years ago, graphyne and its family (viz.graphdiyne, graphyne-3, etc.), as hypothetical C allotropes, were theoretically predicted to be semiconductors with a layered structure.Recently, graphdiyne was successfully synthesized on the surface of copper via a cross-coupling reaction using hexaethynylbenzene.Graphdiyne, as a new two-dimensional carbon material with semiconductor properties and a unique porous structure, is more advantageous than graphene for nanoelectronic and biosensing applications.As the first discovered semiconducting two-dimensional carbon material, with independent intellectual property rights in China, graphdiyne has great research significance.Compared with graphene, graphdiyne has a unique structure with larger pores composed of high π-conjugated acetylenic bonds, which may facilitate strong adsorption to biomolecules.Therefore, further research is needed to reveal how the physical properties of graphdiyne can be modulated effectively to meet the requirements of practical applications.The interaction between biological molecules and materials is an important subject of research in condensed matter physics and materials science.Detailed understanding of the interactions between graphdiyne and small molecules may facilitate the development of advanced biological applications such as biosensors for the detection of biomolecules and living cells, drug delivery systems, and cell imaging technologies.In sensitive analysis, the ultimate goal is to achieve reliable detection of trace amounts of molecules.In this work, first-principles calculations were employed to investigate the electronic structure of graphdiyne nanoribbons and the adsorption of graphdiyne to small molecules.To improve the chemical response of graphdiyne to single molecules, we considered modifying graphdiyne by doping 3d transition metal atoms.We chose Sc and Ti, which have the largest adsorption energies on graphdiyne, and studied the room-temperature stabilities of Sc-and Ti-doped graphdiyne and the possibility of using Sc-and Ti-doped graphdiyne as materials for molecular sensing.Finally, we investigated the interaction between graphdiyne and amino acid molecules and discovered that the dispersion force plays a large role in the interaction.The influence of amino acids on the electronic transport properties of graphdiyne was also studied, and the potential applications of graphdiyne to biosensors were investigated.