Twisted bilayer graphene (tBLG) has recently attracted growing interest due to its unique twist-angle-dependent electronic properties. The preparation of high-quality large-area bilayer graphene with rich rotation angles would be important for the investigation of angle-dependent physics and applications, which, however, is still challenging. Here, we demonstrate a chemical vapor deposition (CVD) approach for growing high-quality tBLG using a hetero-site nucleation strategy, which enables the nucleation of the second layer at a different site from that of the first layer. The fraction of tBLGs in bilayer graphene domains with twist angles ranging from 0° to 30° was found to be improved to 88%, which is significantly higher than those reported previously. The hetero-site nucleation behavior was carefully investigated using an isotope-labeling technique. Furthermore, the clear Moiré patterns and ultrahigh room-temperature carrier mobility of 68,000 cm² V⁻¹ s⁻¹ confirmed the high crystalline quality of our tBLG. Our study opens an avenue for the controllable growth of tBLGs for both fundamental research and practical applications.

Numerical simulations confirm that gas-phase dynamics is an important integrant of the mechanism of graphene growth via chemical vapour deposition.

The microscopic-scale Richtmyer–Meshkov instability (RMI) of a single-mode dense-gas interface is studied by the molecular dynamics approach. Physically realistic evolution processes involving the non-equilibrium effects such as diffusion, dissipation, and thermal conduction are examined for different shock strengths. Different dependence of the perturbation growth on the shock strength is found for the first time. Specifically, the amplitude growths for cases with relatively lower shock Mach numbers (Ma = 1.9, 2.4, 2.9) exhibit an evident discrepancy from a very early stage, whereas for cases with higher Mach numbers (Ma = 4.9, 9.0, 16.0), their amplitude variations with time match quite well during the whole simulation time. Such different behaviors are ascribed to the viscosity effect that plays a crucial role in the microscale RMI. The compressible linear theory of Yang et al. [“Small amplitude theory of Richtmyer–Meshkov instability,” Phys. Fluids 6(5), 1856–1873 (1994)] accounting for the viscosity dissipation provides a reasonable prediction of the simulated linear growth rate. Furthermore, a modified compressible nonlinear model [Q. Zhang et al., “Quantitative theory for the growth rate and amplitude of the compressible Richtmyer–Meshkov instability at all density ratios,” Phys. Rev. Lett. 121, 174502 (2018)] considering both the viscosity effect and the corrected linear growth rate is proposed, which gives an excellent forecast of the linear and nonlinear growths of the present microscale RMI.

Wind-driven rain (WDR) on building facades may lead to water penetration, cladding damage, structural cracking, etc., which affect the durability of the claddings. This study aims to develop a numerical approach to the evaluation of WDR on tall building envelopes based on large eddy simulations (LESs) and a Eulerian multiphase model. The present method utilizes the concept of the multiphase model to deal with rain and wind, and both wind and rain motions as well as their interactions are treated under the Euler frame, which can significantly reduce the complexity in evaluations of WDR and simplify boundary condition treatments. Besides these advantages, unsteady-state WDR information such as the transient catch ratio of WDR, the spatial and temporal distributions of rain intensity, etc., can be predicted by the LES. A validation study shows that the simulation results agree well with the available experimental data, verifying the accuracy of the simulation approach based on the Eulerian multiphase...