SERS-from-scratch: An electric field-guided nanoparticle assembly method for cleanroom-free and low-cost preparation of surface-enhanced Raman scattering substrates

Surface-enhanced Raman scattering (SERS) has been widely reported to improve the sensitivity of Raman spectra. Ordinarily, the laser is focused on the sample to measure the Raman spectrum. The size of the focused light spot is comparable with that of micro-nano structures, and the number of micro-nano structures contained in the light spot area (defined as duty cycle) will severely affect the spectrum intensity. In this study, flower-like silver nanostructures were fabricated with a soft lyotropic liquid crystal template in order to investigate the effect of duty cycle. They were observed under a scanning electron microscope, and their spectrum enhancement factor was computed with the obtained Raman spectrum. Then, their duty cycles were measured using a SERS substrate at different locations. A formula was derived to represent the relation between the duty cycle of the nanoflowers and the Raman spectral intensity. This work could promote the actual applications of SERS in high-sensitivity spectrum testing.

show abstract

“…The enhancement effect of the SERS material may be evaluated in terms of EF, which can be calculated as follows [41][42][43]:…”

Section: Sers Enhancement Factor Calculationmentioning

confidence: 99%

Effect of the Duty Cycle of Flower-like Silver Nanostructures Fabricated with a Lyotropic Liquid Crystal on the SERS Spectrum

et al. 2021

View full text Add to dashboard Cite

show abstract

“…As these substrates were only recently developed, much of the work to date has been focused on understanding the fundamentals of nanostructure growth. [ 11–13 ] Raveendran's most recent work presents the underlying electrochemical reactions and several reaction parameters that are critical to Ag nanostructure formation. [ 11 ] Ag + reduction at the cathode is balanced by the oxidation of citrate (provided in the form of trisodium citrate) at the anode, as shown in Equations () and (), respectively.…”

Section: Introductionmentioning

confidence: 99%

Electrochemically deposited silver nanostructures for use as surface‐enhanced Raman scattering (SERS) substrates in point‐of‐need diagnostic devices

2021

Self Cite

View full text Add to dashboard Cite

In a world that increasingly demands answers in real‐time, there exists a distinct need for chemical sensors that can quickly and efficiently detect substances with high sensitivity and selectivity. To address this need, we use surface‐enhanced Raman scattering (SERS) as a powerful analytical technique that can provide ultrasensitive and versatile chemical detection on a mobile platform when implemented on a handheld Raman spectrometer. However, the large laser spot size of handheld Raman spectrometers requires SERS substrates of sufficient surface area. Here, we present a facile method for electrodepositing nanostructured silver (Ag) SERS substrates onto silicon microchips. In this method, silver ions are continuously reduced from a large volume of solution in an apparatus resembling a batch electrochemical reactor. The straightforward protocol is scalable, fast, and reproducible. Further, we investigate the influence of temperature and fluid agitation on the growth of Ag nanostructures with the intention of maximizing surface area coverage. We observe an increase in lateral nanostructure growth from heating due to an increase in the diffusion coefficient. However, no significant increase in lateral nanostructure growth is observed from stirring the reagent solution. Despite the absence of trends in lateral growth, we find that high agitation levels promote the growth of extraneous Ag structures on top of the nanostructured film, indicating the presence of a boundary layer at the silicon surface. Further, we find that increased diffusion rates at high temperatures shift the reaction towards the limits of the mass transfer‐controlled regime.

show abstract

“…The use of plasmonic metal nanostructures has readily improved these vibrational signals by providing both chemical and electromagnetic enhancements. 2,[5][6][7][8] Although the SERS enhancement mechanisms are complicated, the electromagnetic enhancement (EM) effect is thought to explain the strongest contribution of the molecular vibration at the surface of metal particles by plasmon resonance excitation. Further signal enhancement can be achieved by properly controlling the interparticle coupling environments and multiple junctions between nanoscale structures (i.e., hot spots), where extraordinarily strong local electric elds are oen generated near the vicinity of nanoscale materials possessing surface plasmon resonance (SPR).…”

Section: Introductionmentioning

confidence: 99%

“…2,6,9,10 The signal enhancements by SERS have been highly tuned by the characteristics of the substrates associated with the plasmonic properties and morphology of the nanostructures. 1,3,8,11,12 As such, enormous efforts have been made to the development of structurally diverse plasmonic materials and new fabrication strategies capable of nely tuning their arrangements for SERS enhancement. These approaches readily improve the SERS sensitivity, but oen require complicated multiple steps to control morphological features, signicantly limiting their practical use as rapid and inexpensive SERS substrates.…”

Section: Introductionmentioning

confidence: 99%

Sandwiching analytes with structurally diverse plasmonic nanoparticles on paper substrates for surface enhanced Raman spectroscopy

et al. 2019

View full text Add to dashboard Cite

show abstract

SERS-from-scratch: An electric field-guided nanoparticle assembly method for cleanroom-free and low-cost preparation of surface-enhanced Raman scattering substrates

Cited by 24 publications

References 59 publications

Effect of the Duty Cycle of Flower-like Silver Nanostructures Fabricated with a Lyotropic Liquid Crystal on the SERS Spectrum

Effect of the Duty Cycle of Flower-like Silver Nanostructures Fabricated with a Lyotropic Liquid Crystal on the SERS Spectrum

Electrochemically deposited silver nanostructures for use as surface‐enhanced Raman scattering (SERS) substrates in point‐of‐need diagnostic devices

Sandwiching analytes with structurally diverse plasmonic nanoparticles on paper substrates for surface enhanced Raman spectroscopy

Contact Info

Product

Resources

About