scholarly journals Surface-Enhanced Infrared Absorption of o-Nitroaniline on Nickel Nanoparticles Synthesized by Electrochemical Deposition

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Yufang Niu ◽  
Jie Yao ◽  
Keyu Wang
Keyword(s):  
Infrared Absorption ◽  
Indium Tin Oxide ◽  
Nickel Nanoparticles ◽  
Ph Value ◽  
Glass Plate ◽  
Nickel Sulfate ◽  
Nickel Chloride ◽  
Attenuated Total Reflection ◽  
Enhancement Effect ◽  
Surface Enhanced

Nickel nanoparticles were electrochemically deposited on indium-tin oxide (ITO) coated glass plate in a modified Watt’s electrolyte. The surface-enhanced infrared absorption (SEIRA) effect of the nanoparticles was evaluated by attenuated total reflection spectroscopy (ATR-FTIR) using o-nitroaniline as a probe molecule. Electrodeposition parameters such as deposition time, pH value, and the type of surfactants were investigated. The morphology and the microstructure of the deposits were characterized by the field emission scanning electron microscope (FESEM) and the atomic force microscope (AFM), respectively. The results indicate that the optimum parameters were potential of 1.3 V, time of 30 s, and pH of 8.92 in the solution of 0.3756 mol/L diethanolamine, 0.1 mol/L nickel sulfate, 0.01 mol/L nickel chloride, and 0.05 mol/L boric acid. The FESEM observation shows that the morphology of nickel nanoparticles with best enhancement effect is spherical and narrowly distributed particles with the average size of 50 nm. SEIRA enhancement factor is about 68.

scholarly journals Surface Enhanced Infrared Absorption Studies of SiO2–TiO2–Ag Nanofibers: Effect of Silver Electrodeposition Time on the Amplification of Signals

Crystals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 563
Author(s):  
Blanca Selenis Cabello-Ribota ◽  
Rurik Farías ◽  
Simón Yobanny Reyes-López
Keyword(s):  
Raman Spectroscopy ◽  
Infrared Spectroscopy ◽  
New Media ◽  
Infrared Absorption ◽  
Indium Tin Oxide ◽  
Amplification Factor ◽  
Sol Gel ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Surface Enhanced

Surface Enhanced on Infrared Absorption (SEIRAS) and Raman Spectroscopy (SERS) are nondestructive analytic techniques used to detect low concentrations and recognize the fingerprints of molecules. The recognition of the absorption from samples by conventional infrared spectroscopy (IR) via Attenuated Total Reflection (ATR) is difficult for molecules with a low signal strength. However, developed structures with SERS and SEIRAS effect present problems such as high cost, low stability, and low compatibility. Research into new media to obtain greater amplification is largely based on the creation of nanoscale structures with symmetrical arrangements and reproducible distances, resulting in aggregates of nanoparticles that help generate hot spots which are active for amplification. The sol-gel and electrospinning method for the obtention of ceramics provides an alternative means by which to produce said substrates. Fibers of nanometric scale provide an increase of surface area which allows more contact to occur with analytes. Consequently, in this study, a silica-titania-silver nanostructured support that amplifies signal intensity for Raman and infrared spectroscopy was developed. The silica-titania support was developed by sol-gel and electrospinning techniques, and the as spun fibers were treated at 800 °C. Then, the ceramic fibrous membrane was placed on conductive indium tin oxide plastic to be doped with silver using an electroplating technique, varying the silver nitrate concentration (5, 10 and 20 mM), as well as electrodeposition times (1, 2, 5 and 10 min), with a constant voltage (1 V). Twelve different supports were obtained that showed amplification. The enhancement of infrared signals from pyridine and crystal violet molecules adsorbed on silica-titania-silver (SiO2–TiO2–Ag) nanofibers was studied in situ by Attenuated Total Reflection-Fourier Transformed Infrared Spectroscopy (ATR-FTIR). The highest amplification was obtained by the support doped at 10 min in a 10 mM concentration, with an amplification factor of 2.74 in the band localized at 3301 cm−1. In Raman spectroscopy, the highest amplification factor was 27.03, on the support doped for 5 min at a concentration of 5 mM.

scholarly journals Study of surface-enhanced infrared absorption spectroscopy (SEIRAS) of black inkjet prints using silver colloid

2017 ◽  
Vol 10 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Michal Oravec ◽  
Katsuya Miura ◽  
Michal Čeppana
Keyword(s):  
Absorption Spectroscopy ◽  
Infrared Absorption ◽  
Document Analysis ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Infrared Absorption Spectroscopy ◽  
Silver Colloid ◽  
Absorption Signal ◽  
Surface Enhanced ◽  
Scanning Electron

Abstract Only black inkjet prints were studied with regard to forensic examination of documents. We analysed twenty-one inkjet prints using surface-enhanced infrared absorption spectroscopy (SEIRAS). The present paper deals with micro-destructive document analysis based on silver nanoparticles (AgNPs) use to obtain surface enhanced ATR-FTIR (attenuated total reflection - Fourier transform infrared) spectra directly from the document. For this experiment, AgNPs in colloid form was applied. AgNPs for SEIRAS analyses were synthesised and afterwards analysed by scanning electron microscopy (SEM). The purpose of the enhancement of colloids was to improve the resolution of the absorption signal of the analysed samples from noise. In the experiment, the obtained ink ATR-FTIR spectra, with and without silver treatment, were significantly affected by the paper base.

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