掺杂石墨烯吸附特性的第一性原理研究

利用第一性原理方法研究了一氧化碳分子在本征和硼、氮、铝、磷掺杂的有限尺寸石墨烯上的吸附机理.结果表明，石墨烯作为一氧化碳传感器时的性能依赖于掺杂元素.本征、硼和氮掺杂石墨烯吸附一氧化碳时的吸附能较低，为物理吸附.铝、磷掺杂石墨烯的吸附能显著提高，比本征、硼和氮掺杂时高出约一个数量级，且铝和磷原子从石墨烯中突出，使其发生局部弯曲.铝掺杂石墨烯增强了石墨烯与一氧化碳分子之间的相互作用，可以提高石墨烯的气敏性和吸附能力，是一氧化碳传感器的最佳候选材料之一.

First principles study on the adsorption characteristics of doped graphene

The adsorption mechanism of CO on pristine graphene and B-, N-, Al-, P-doped finite size graphene sheets were investigated using first principle method. The results show that the sensing performance of graphene as a CO sensor strongly depends on the dopants. And the adsorption energy is lower indicating physisorption mechanism for CO molecule adsorption on pristine, B- and N-doped graphene sheets. The adsorption energy of the Al- and P-doped graphene were found to be significantly increased, about one order of magnitude higher than that pristine, B- and N-doped graphene, and Al and P atoms protrude out of the graphene sheet and make locally buckled. The Al-doped graphene enhances the interaction between graphene and CO molecule and can improve the gas sensitivity speed and adsorption capacity of graphene as the optimal candidate for CO sensing.