Abstract In the present work the effect exerted by N-doping on parameters characterizing dopamine adsorption on modified graphene substrate is theoretically studied. Moreover, an analysis of dipole moment properties of dopamine/N-doped-graphene system was performed in order to predict the feasibility of N-doped graphene system as a sensor material. Dopamine molecule anchors preferentially according to parallel modes of adsorption, stabilizing predominantly through dispersive interactions and showing very small atomic charges. On the other hand, the anchoring on sites with one nitrogen atom in the carbon monovacancy border is much more favored than on other sites, owing to non-covalent hydrogen bonding interactions. An analysis carried out about the modifications of polarization along the normal direction to the basal planes of graphene-based substrates, considering the most representative parallel modes of dopamine adsorption, indicated that N-doping enhances such dipole moment changes, compared with regular graphene, particularly when dopamine anchors on N-graphitic defects with four nitrogen atoms as impurities and N-pyridinic defects with one impurity nitrogen atom.

中文翻译：

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多巴胺/N 掺杂石墨烯系统中的偶极矩效应

摘要 在目前的工作中，从理论上研究了 N 掺杂对表征多巴胺在改性石墨烯基底上吸附的参数的影响。此外，还对多巴胺/N 掺杂石墨烯系统的偶极矩特性进行了分析，以预测 N 掺杂石墨烯系统作为传感器材料的可行性。多巴胺分子根据平行吸附模式优先锚定，主要通过分散相互作用稳定并显示非常小的原子电荷。另一方面，由于非共价氢键相互作用，在碳单空位边界中具有一个氮原子的位点上的锚定比在其他位点上更有利。