2017/07/31 by Pierce Maguire, Daniel S. Fox, Daniel Fox +12
Chemistry · Materials Science · Physics and Astronomy · #2D Materials and Applications #Chemistry #Geology #Graphene research and applications #Ion #Irradiation #MXene and MAX Phase Materials #Materials science #Monolayer #Nanotechnology #Nuclear physics #Organic chemistry #Physics #Sizing #Substrate (aquarium) #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.98.134109
published as Phys. Rev. B 98, 134109 (2018) · 11 pages, 6 figures
arxiv created 2018/04/17 · openalex created_date 2018/04/24 · openalex publication_date 2018/10/18 · arxiv updated 2018/10/24 · openalex updated_date 2026/08/05
Precise and scalable defect engineering of two-dimensional (2D) nanomaterials is acutely sought after in contemporary materials science. Here, we present defect engineering in monolayer graphene and molybdenum disulfide (MoS2) by irradiation with noble gas ions at 30 keV. Two ion species of different masses were used in a gas field ion source microscope: helium (He+) and neon (Ne+). A detailed Raman spectroscopy study was performed and a defect activation model applied with marked differences between the ion systems at a given dose. We propose that disparities between the ion systems are explained by different defect yields and defect sizes. Expanding on existing models, we suggest that the average defect size is smaller for supported than freestanding graphene and that the rate of defect production is larger. We infer that low-energy secondary atoms from the substrate play a significant role in defect production, creating smaller defects relative to those created by the primary ion beam. Furthermore, a similar model was also applied to supported MoS2, another promising member of the 2D material family. Defect yields for both ions were obtained for MoS2, demonstrating their different interaction with the material and facilitating comparison with other irradiation conditions in the literature.