Seed-Mediated Electroless Deposition of Gold Nanoparticles for Highly Uniform and Efficient SERS Enhancement

Abstract

A seed-mediated electroless deposition (SMED) approach for fabrication of large-area and uniform gold nanoparticle films as efficient and reproducible as surface-enhanced Raman scattering (SERS) substrates was presented. This approach involved a seeding pretreatment procedure and a subsequent growth step. The former referred to activation of polylysine-coated glass slides in gold seed solution, and the latter required a careful control of the reactant concentration and reaction time. With the aid of gold seeds and appropriate reaction conditions, a large-area and uniform nanofilm with evenly distributed gold nanoparticles (Au NPs) was formed on the surface of the substrates after adding a mixed solution containing ascorbic acid and trisodium citrate. The morphology of the Au nanofilm was examined by scanning electron microscopy. The size evolution of Au NPs on the surface of the substrates was analyzed in detail. The nanofilm substrate was prepared by reaction conditions of the seeded activation process: 10 mL ascorbic acid and trisodium citrate mixture and 30 min of soaking time, which exhibited an excellent uniformity and reproducibility of SERS enhancement with relative standard deviation (RSD) values of less than 8% (particularly, a RSD value of 3% can be reached for the optimized measurement). Compared to the common electroless deposition, the seed-mediated electroless deposition possessed inherent advantages in controllability, reproducibility, and economic benefit.

Immobilization and 3D Hot-Junction Formation of Gold Nanoparticles on Two-Dimensional Silicate Nanoplatelets as Substrates for High-Efficiency Surface-Enhanced Raman Scattering Detection

“…It has been reported that the electromagnetic behaviors of AgNP arrays are virtually enhanced due to the spaces between the particle arrays because parts of the two- and three-dimensional (2D and 3D, respectively) hot-junctions formed are smaller than 10 nm. Fabrication methods of AuNPs include electron beam lithography [16], chemical vapor deposition [17], and the oxidation-reduction reaction [18]. Meanwhile, there is growing interest in the use of biodegradable and sustainable materials [19] for SERS.…”

SERS background imaging – A versatile tool towards more reliable SERS analytics

“…This allows to obtain a SERS signal from at least one or two hot spots in 78% or 37% of the measurements, respectively ( Figure S6a). However, as already mentioned by Crawford et al 28 increasing the laser spot size above the objective-de ned size requires speci c technical equipment to widen the laser spot and concomitantly requires an increase in the laser power, which is not possible in all commercially available Raman spectrometers.…”

“…For example, the reproducibility of SERS signals can be highly dependent of the size of the laser spot. Sampling errors or undersampling occurs when the size of the analysed area is below that needed to reliably represent the composition of the sample 28 . Heterogeneous SERS substrates therefore require an illumination with large laser spot sizes to obtain reliable results.…”

3D-MID Technology for Surface Modification of Polymer-Based Composites: A Comprehensive Review

“…Higher concentration of activator or too long immersion time lead to improper activation which probably cause poor metallic bonding. There are many commercial catalysts that can be used in the activation process as showed in Table 8 [ 282 , 283 , 284 , 285 ]. Generally, the electroless plating is regarded as a dehydrogenation reaction since the hydrogen may develops simultaneously with metal reduction.…”