Novel Cu-Ag bimetallic porous nanomembrane prepared from a multi-component metallic glass

Porous nanomembranes (PNMs) have wide applications in templates, filtration, transport and separation, water treatment, drug delivery and sensing, but the preparation of metallic PNMs has been scarcely reported due to the technical difficulty and the easy oxidization during the preparation and preservation processes. In present work, ultrathin Cu-Ag bimetallic PNMs with thicknesses of ∼5 to 50 nm, an area larger than 20 square micron, pore diameters of ∼10 to 20 nm and ligament feature sizes of ∼30 to 50 nm have been prepared from a Zr<inf>48</inf>Cu<inf>36</inf>Ag<inf>8</inf>Al<inf>8</inf> metallic glass by chemical dealloying assisted with ultrasonic vibration. The structural evolution and formation mechanism of the Cu-Ag bimetallic PNMs were also investigated. The effects of dealloying parameters on the dealloyed samples' morphologies were systematically investigated. The prepared Cu-Ag bimetallic PNMs exhibit good antibacterial activity against E. coli over a wide concentration range. The present result provides an easy and inexpensive method for preparing Cu-Ag PNMs.