Two-step approach for the nanofabrication of highly ordered ultra-long porous gold nanowires with an adjustable porosity for SERS-based sensors

摘要

Recently, nanoporous gold has been pointed out as a promising candidate for the development of SERS-based sensors for the detection of environmental toxins and small molecules. One way to improve the detection ability of such sensors is by engineering the porosity and shape of nanoporous materials. In this work we report on a versatile two-step approach for the synthesis of porous nanowires involving plasma deposition of gold-copper alloy on a nanograted substrate followed by a selective electrochemical etching. The relevance of this approach is its ability to prepare highly ordered ultra-long porous gold nanowires with an adjustable porosity and a length up to the macroscale. The resulting gold porous nanowire exhibits a very high roughness and high specific surface area suitable for highly sensitive detection of small molecules by SERS.