Kong Lingmei, Enders Axel, Rahman Talat S, Dowben Peter A
Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, Theodore Jorgensen Hall, 855 North 16th Street, University of Nebraska, PO Box 880299, Lincoln, NE 68588-0299, USA.
J Phys Condens Matter. 2014 Nov 5;26(44):443001. doi: 10.1088/0953-8984/26/44/443001. Epub 2014 Oct 7.
Current studies addressing the engineering of charge carrier concentration and the electronic band gap in epitaxial graphene using molecular adsorbates are reviewed. The focus here is on interactions between the graphene surface and the adsorbed molecules, including small gas molecules (H(2)O, H(2), O(2), CO, NO(2), NO, and NH(3)), aromatic, and non-aromatic molecules (F4-TCNQ, PTCDA, TPA, Na-NH(2), An-CH(3), An-Br, Poly (ethylene imine) (PEI), and diazonium salts), and various biomolecules such as peptides, DNA fragments, and other derivatives. This is followed by a discussion on graphene-based gas sensor concepts. In reviewing the studies of the effects of molecular adsorption on graphene, it is evident that the strong manipulation of graphene's electronic structure, including p- and n-doping, is not only possible with molecular adsorbates, but that this approach appears to be superior compared to these exploiting edge effects, local defects, or strain. However, graphene-based gas sensors, albeit feasible because huge adsorbate-induced variations in the relative conductivity are possible, generally suffer from the lack of chemical selectivity.
本文综述了当前利用分子吸附物对外延石墨烯中的载流子浓度和电子带隙进行工程调控的研究。这里重点关注石墨烯表面与吸附分子之间的相互作用，包括小分子气体（H₂O、H₂、O₂、CO、NO₂、NO和NH₃）、芳香族和非芳香族分子（F4-TCNQ、PTCDA、TPA、Na-NH₂、An-CH₃、An-Br、聚乙二胺（PEI）和重氮盐）以及各种生物分子，如肽、DNA片段和其他衍生物。接下来讨论基于石墨烯的气体传感器概念。在回顾分子吸附对石墨烯影响的研究时，很明显，利用分子吸附物不仅可以对石墨烯的电子结构进行强调控，包括p型和n型掺杂，而且这种方法似乎比利用边缘效应、局部缺陷或应变的方法更具优势。然而，基于石墨烯的气体传感器虽然可行，因为吸附物会导致相对电导率发生巨大变化，但通常缺乏化学选择性。
