环境影响下碳基纳米材料吸附生物小分子的识别研究

To promote possible applications of the carbon based nano-material, in particular the recognition mechanism in life process. In this project, we will focus on the problem of the physical recognition mechanism of biological small molecules adsorbed on the perfect and defect surface of the carbon based nano-material in different environment, take the carbon-based material adsorption system has been more attention, as the research object. Through the first principle of quantum theory calculation, especially the density functional tight binding method with a dispersion term, making the intermolecular interaction had a clear embodiment. Based on the quantum level, we calculate the electronic properties difference of adsorption systems, explore the impact of the defect, acid and alkali environment for the interaction, so as to reveal the various electronic characteristics, phenomenon, physical mechanism of the process, fundamentally explain its mechanism and reasons. The research results of the project have an important meaning for the files such as life science and material science, and also provide fundamental knowledge for designing new molecular sensing devices.

为了探索碳基纳米材料的潜在应用，尤其是在生命过程中的识别机制。本项目针对生物小分子在不同环境条件下吸附于完美及带缺陷的碳基纳米材料表面的物理识别机制问题，以一直以来被广泛关注的碳基材料吸附体系为研究对象，通过量子第一性原理计算，尤其是采用带有色散项的紧束缚密度泛函方法，使得分子间相互作用得到明确体现，在量子水平上计算生物小分子吸附于不同表面的碳基材料的电子特性差异，探索缺陷及酸碱环境对相互作用的影响，从而揭示吸附体系在相互作用下的各种电子特性、现象、过程的物理机制，从根本上解释其作用机理及各种现象产生的原因。本项目的研究成果对生命科学和材料科学等领域具有重要的意义，也为分子传感器的设计提供基础性认识。

为了探索外界环境对石墨烯纳米材料的影响，尤其是自然界中广泛存在的非完美的缺陷引起的量子效应机制。本项目基于密度泛函理论中的PBE-D3方法，分别讨论了引入四种不同类型的缺陷（dgr5577，dgr59，dgr585，dgrad）时，缺陷本身对完美石墨烯底片的电子态等量子效应影响，以及将苯环吸附于不同缺陷类型的石墨烯基底所展现的表面物理识别机制问题。很有趣的，我们发现引入缺陷后，单层石墨烯的基态仍为闭壳层单重态，且dgr585缺陷结构弯曲程度最为显著，进一步的拉曼光谱特征峰分析，可以清晰的区分不同缺陷结构之间的差异；另一方面，当吸附苯环时，dgrad类型吸附体系从物理吸附转变为化学吸附，而其他吸附构象均为物理吸附，进一步的吸附能，拉曼谱，电荷转移及态密度等量子特性分析均证实这一结论。本项目研究成果希望对材料科学等领域提供理论基础，也希望对分子传感器件的设计提供基础性的认识。