[15a-PA01-1~56] 17 ナノカーボン（ポスター）

▲ [15a-PA01-28] First-principles Study on Strain-induced Change of Adsorption Behaviors
of NO₂ Molecules on Graphene

〇(D)Meng Yin¹、Xiangyu Qiao¹、Lei Wang²、Ken Suzuki³、Hideo Miura³ (1.Dept. of Finemechanics , Tohoku Univ、2.Dept. of Physics, Beijing University of Science and Technology、3.Fracture and Reliability Research Institute (FRRI), Tohoku Univ)

キーワード：Graphene, Adsorption of nitrogen dioxide, Strain

Real time monitoring of nitrogen dioxide (NO₂) is indispensable for protection of environmental pollution and early detection of respiratory diseases. Graphene, a single atomic layer of carbon atoms arranged in a hexagonal lattice, has gained significant attention as a platform for detecting gases due to its large change of electrical resistance by adsorption of gas molecules on it. In previous studies, Schedin’s group found that it was possible to detect nitrogen dioxide gas with resolution of 1 ppb. However, lack of selectivity made it difficult to detect specific molecules in complex environments which consists of plural kinds of molecules. No effective methods for improving the selectivity have been developed yet. Recently, the authors found that the effective adsorption energy changed significantly under the application of mechanical stress or strain. In addition, the strain-induced change was validated by using a test graphene-base sensor on a flexible substrate PDMS under the cyclic application of strain up to 30%. These findings suggested that strain-controlled graphene a strong candidate for a highly sensitive and selective nitrogen dioxide sensor. In this study, first-principles calculation was applied to the investigation of the strain-induced change of the adsorption energy of NO₂ molecule on graphene. It was found that the strain-sensitivity of NO₂ adsorption energy on the graphene surface was much larger than that of other molecules. The amount of adsorption energy decreased monotonically under the application of tensile strain, while it increased under compressive strain. These findings suggested that strain-controlled graphene has strong potential to be a highly sensitive and selective NO₂ sensor with important implications for air quality monitoring and early detection of respiratory diseases.