Platinum Films with Controlled 3‐Dimensional Nanoscopic Morphologies and Their Effects on Surface Enhanced Raman Scattering

Abstract

The synthesis of Pt thin films with a controlled nanoscopic architecture that can support surface enhanced Raman scattering (SERS) is reported. The syntheses are achieved by replicating the pores of a type of mesoporous silica thin film whose pore structure could be described as a regular array of vertical channels of approximately 9 nm in diameter and their interconnections, forming a 3-dimensional pore network. Electrochemical deposition into the pores followed by the removal of the templates produced Pt films composed of arrays of vertically standing Pt nanorods with narrow gaps between them. The 3-dimensional nanostructure increases the surface area and enables the Pt film to absorb visible light. SERS studies of rhodamine 6G and benzenethiol on such Pt films as substrates reveals that the control of the nanostructure is critical for the SERS effect.

Templated syntheses of Pt thin films with feature sizes of 3, 6 and 9 nm and their effects on SERS

“…One of the reasons for this may be that the closely spaced Pt nanorods interact with one another to extend the SPR to longer wavelengths. The extension of the SPR to longer wavelengths has been demonstrated experimentally and theoretically on Pt‐9.…”

“…Our group has introduced a novel method to create nanostructured thin films by using mesoporous silica thin films (MSTFs) as templates . Filling the pores with SERS‐active metals and removing the template can produce nanostructured thin films.…”

“…We have previously reported the SERS activity of nanostructured Pt films with the feature size of 9 nm focusing on the effects of the amount of Pt and the details of the nanostructures . In this study, we synthesized Pt thin films with the feature sizes controlled to be 3, 6 and 9 nm and investigated the effects of the feature size on SERS.…”

Synergistic Effects between Gold Nanoparticles and Nanostructured Platinum Film in Surface-Enhanced Raman Spectroscopy

“…A scheme of synthesis and a scanning electron microscopy (SEM, JEOL JSM-7100) image of a nanostructured Pt thin film are in Figure S1. More details of the synthesis of MSTF and the nanostructured Pt thin film can be found in our previous papers. − …”

Low-Cost Fabrication of Pt Thin Films with Controlled Nanostructures and Their Effects on SERS

“…Although there have been a number of cases in which anodized aluminum oxide templates are used to synthesize nanorods, the main focus has been on the control of the shape and size of the nanorods, not on the formation of the array structure of nanorods [30][31][32][33]. In this regard, mesoporous thin film templates appear to be advantageous because nanostructured films with very fine features <10 nm in regular arrays are possible [24][25][26][27][28][29][30][31][32][33][34][35][36][37]. Furthermore, because of the various pore morphologies, mesoporous thin films can provide unique opportunities to explore the effects of various nanostructures on the SERS.…”