Directional Manufacturing of Defect Mitigation and Large-Scale Single-Crystalline Metal Foils via Gas Flow Optimization toward Commercialization.

Single-crystalline metals, with their distinctive symmetries, are the ideal medium for high-order molecular arrangement and the diminishing of grain boundaries and defect sites coupled with high anisotropy. However, conventional synthesis via bulk growth or epitaxial deposition remains complex, costly, and difficult to scale. Here, we report a simple and inexpensive strategy as an alternative to conventional strategies for manufacturing single-crystalline metal foils. Miraculously, by miniaturization of grain boundaries and promoting surface energy minimization during the rotation of the crystal lattice followed by the consumption of neighboring grains, high-quality and large-scale single-crystalline metal foils (Cu(111), Ni(111)) were obtained via vertically suspended chemical vapor deposition (CVD) annealing of polycrystalline metal foils. This discovery offers a potential strategy for manipulating and producing large-scale metal foils that may be used for industrial-scale applications.