tailieunhanh - Báo cáo hóa học: " Mechanical characterization of nanoindented graphene via molecular dynamics simulations"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Mechanical characterization of nanoindented graphene via molecular dynamics simulations | Fang et al. Nanoscale Research Letters 2011 6 481 http content 6 1 481 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Mechanical characterization of nanoindented graphene via molecular dynamics simulations Te-Hua Fang1 Tong Hong Wang2 Jhih-Chin Yang3 and Yu-Jen Hsiao4 Abstract The mechanical behavior of graphene under various indentation depths velocities and temperatures is studied using molecular dynamics analysis. The results show that the load elastic and plastic energies and relaxation force increased with increasing indentation depth and velocity. Nanoindentation induced pile ups and corrugations of the graphene. Resistance to deformation decreased at higher temperature. Strong adhesion caused topological defects and vacancies during the unloading process. Keywords molecular dynamics nanoindentation graphene mechanical properties Introduction Graphene has received a lot of attention due to its good mechanical and electromagnetic properties 1-3 including a zero electron bandgap a high electron emission rate and elastic scattering 4-6 . Atomic-scale graphene can be fabricated using micro-mechanical chop crack 7 thermal expansion 8 and extension growth 9 techniques. Studies 10-13 have found that the bandfield effect of a 10-nm-thick graphene sheet is similar to that of a small less than nm in diameter nanographite particle. Novoselov and Geim 7 used graphene to fabricate a small crystal tube. Monolayer graphene is considered a suitable material for investigating two-dimensional quantization phenomena such as temperature-trigger plasma 14 quantization absorption spectrum 15 and the fractional quantum Hall effect 16 . In addition the hexagonal symmetric structure of graphene makes it a candidate material for nano devices. Many studies 17-25 have focused on the chemical functionalization of graphene especially on the effect of absorbed atoms on the electronic and chemical properties of graphene. However the