论文标题
用芳香族分子诱导的石墨烯纳米纤维中的均匀电导效应：新型化学传感器的基础
Even-odd conductance effect in graphene nanoribbons induced by edge functionalization with aromatic molecules: Basis for novel chemosensors
论文作者
论文摘要
从理论上讲，我们研究了扶手椅和曲折石墨烯纳米纤维（GNRS）中的电子传输，其长度增加的p-多苯基和多乙烯基团化学功能化。我们最近的邻居紧密结合计算表明，根据官能团中的芳族环的数量甚至是奇数，与原始GNR相比，与相应隔离分子的能级相匹配的能量与相应分离的分子的能级相匹配或完全减少了一个量子。这种均匀的效应显示出源自在宾客分子的电子状态之间的微妙相互作用，该效果在空间上定位在结合位点和宿主纳米替比的结合位点。接下来，我们通过采用更准确的紧密结合哈密顿人以及密度功能理论计算来概括我们的发现，并认真讨论观察到的物理效应对所采用理论水平的鲁棒性。我们的工作对与石墨烯纳米纤维边缘的芳族分子对电子传输性能的边缘的影响有了深入的了解，这是一个对基于石墨烯的化学传感器的前瞻性实现起作用的问题。
We theoretically investigate the electron transport in armchair and zigzag graphene nanoribbons (GNRs) chemically functionalized with p-polyphenyl and polyacene groups of increasing length. Our nearest-neighbor tight-binding calculations indicate that, depending on whether the number of aromatic rings in the functional group is even or odd, the resulting conductance at energies matching the energy levels of the corresponding isolated molecule are either unaffected or reduced by exactly one quantum as compared to the pristine GNR, respectively. Such an even-odd effect is shown to originate from a subtle interplay between the electronic states of the guest molecule that are spatially localized on the binding sites and those of the host nanoribbon. We next generalize our findings by employing more accurate tight-binding Hamiltonians along with density-functional theory calculations, and critically discuss the robustness of the observed physical effects against the level of theory adopted. Our work offers a comprehensive understanding of the influence of aromatic molecules bound to the edge of graphene nanoribbons on their electronic transport properties, an issue which is instrumental to the prospective realization of graphene-based chemosensors.
