Large-Scale Preparation of 2D Metal Films by a Top-Down Approach

2D metal thin films attract extensive attention due to their intriguing physiochemical properties and a broad range of promising applications. Typically, 2D metal films are produced via bottom-up synthetic methods. Herein, a top-down approach that combines accumulative roll bonding (ARB) technique with selective etching is developed for the large-scale preparation of 2D Ta films. First, alternatingly stacked 2D Cu/Ta multilayer structures are prepared by ARB. Then, 2D Ta films are achieved by selective chemical etching of the Cu layers. The as-prepared 2D Ta films with controllable thicknesses range from several tens of micrometers to several tens of nanometers. The thickness of the resultant 2D Ta films can be controlled by ARB technique. Moreover, this top-down approach can be generalized to fabricate other various 2D metal films with a wide range of dimensions.