화학공학소재연구정보센터
Applied Surface Science, Vol.406, 285-293, 2017
A simple technique for direct growth of Au into a nanoporous alumina layer on conductive glass as a reusable SERS substrate
In this paper, we describe a simple technique for direct growth of gold nanoparticles (GNPs) into a nano-structured porous alumina layer on conductive glass slide (PAOCG). PAOCG was attached firmly with a small piece of steel and was then immersed in a HAuCl4 solution. Electro-induced electrons from steel were employed to reduce AuCI4- on PAOCG. The galvanic replacement reaction (GRR) was adopted as the fundamental mechanism for reducing metal precursors. This mechanism was further studied by open circuit potential-time (OCP-t) experiment and the result demonstrated that steel induced the continuous proceeding of this reaction. This strategy presents a simple and general protocol for preparation of metal nanoparticles (MNPs) on conductive glass substrates. The SERS properties of Au/PAOCG were investigated using aqueous crystal violet (CV) and 4-mercaptopyridine (4-Mpy) as probe molecules. Au/PAOCG allowed as low as 10(-9) M CV and 10(-8) M 4-Mpy to be detected. The reusability of this substrate was achieved by measuring the SERS spectrum of the probe molecules followed with a 400 degrees C heat treatment for 10 min to remove the residuals. This substrate could be reused for at least ten cycles without any significantly reduced SERS performance. Therefore, this surface can serve as a portable, durable and reusable SERS substrate and has a potential for commercial applications. (C) 2017 Elsevier B.V. All rights reserved.