Nanoporous Gold Membranes as Robust Constructs for Selectively Tunable Chemical Transport
Daniel A. McCurry, and Ryan C. Bailey J. Phys. Chem. C, Just Accepted Manuscript
Nanopores are promising structures for small volume separations, but often require complex topdown fabrication and are not easily (re)configurable to allow for dynamically tuned separations. Herein we report the first use of nanoporous gold (NPG) membranes as tunable, charge-based separation elements. NPG is fabricated into a robust network of interconnecting pores via simple solution de-alloying. We demonstrate that control over the selective permeation of small molecule analytes can be controlled via three different methods: 1) anion adsorption at the Au surface; 2) pH-tuning of self-assembled monolayer (SAM) charge; and 3) electrochemical oxidation of a redox-active SAM. This simple and versatile membrane system is promising as a dynamically-tunable element for small volume separations.