石墨烯吸附有机分子硝基苯性质的第一性原理研究

摘要

Based on first principle calculation,we have studied the properties of nitrobenzene-adsorbed graphene system.There is large adsorption energy in case of nitrobenzene being parallel to graphene substrate,while relative small adsorption energy is gained when the adsorbed molecule is perpendicular to graphene plane.At the same,in parallel case a slight lattice expansion is generated by adsorption interaction,in contrast to a weak lattice shrink produced by electron transferred from graphene to nitrobenzene in the perpendicular case.Due to relative strong interaction between nitro group and graphene,a doping state emerges when nitrobenzene is adsorbed on graphene plane.This provides a theoretical support to use of the graphene system as a chemical sensor of nitrobenzene molecules.%基于量子力学的第一性原理,我们计算了石墨烯吸附有机分子硝基苯的特性.在吸附体系中,吸附分子平面平行于石墨烯衬底时吸附能最大,同时此吸附导致衬底晶格微弱的膨胀.吸附分子平面垂直石墨烯吸附时,吸附能较小,且衬底晶格有微弱的收缩.由于硝基和石墨烯之间较强的相互作用,吸附结构的能带中出现明显的掺杂态.这说明了石墨烯可以作为有机分子硝基苯的化学传感器件之一.