Improvement of Heat Dissipation in Ag/Ni Substrates for Testing Cu-TiO2/TiO2-Modified Filters Using SERS Spectroscopy

Abstract

Surface-enhanced Raman scattering (SERS) spectroscopy is used to investigate a composition of wash swabs from the Cu-TiO2/TiO2-modified filters with disinfecting ability. Macroporous Si chips coated with conformal 800 nm thick Ni layer and Ag particles (Ag/Ni) are engineered to act as SERS-active substrates. Such substrates are characterized by a moderate reflection band in the visible range and provide an improved heat dissipation from contaminants in wash swabs during SERS study. This prevents thermal-induced destruction of analyzing media for reliable assessment of its composition. The anatase Cu-TiO2 and TiO2 nanoparticles are synthesized using the sol-gel method and characterized via Raman spectroscopy and X-ray diffractometry. The filters are modified with Cu-TiO2/TiO2 nanoparticles and embedded in three-valve facial masks that are worn by a volunteer to breathe for 4 h. Comparative SERS analysis of the filters shows that they slightly destroy chemical bonds in the molecules constituting airborne contaminations upon ceiling day lights, which can be associated with Cu-TiO2 photocatalytic activity. The filters additionally exposed to near-ultraviolet light prominently decrease the intensity of Raman signatures of airborne contaminant due to the presence of pure TiO2.

Ag@AuNP-Functionalized Capillary-Based SERS Sensing Platform for Interference-Free Detection of Glucose in Urine Using SERS Tags with Built-In Nitrile Signal

“…The Raman signals of molecules such as alkyne, nitrile, and cyanide ion in the silent region (1800-2800 cm −1 ) did not overlap with background signals, avoiding interference from those of regular molecules [21][22][23][24]. Thanks to the development of nanomaterials, many new SERS substrates were prepared for SERS sensing detection, and satisfactory detection results were obtained [25][26][27]. For example, Bandarenka's group prepared gold-coated porous silicon nanostructures for molecular analysis via SERS spectroscopy [26].…”

Investigating Laser-Induced Periodic Surface Structures (LIPSS) Formation in Silicon and Their Impact on Surface-Enhanced Raman Spectroscopy (SERS)

“…Three-dimensional multilayered SERS substrates introduce additional plasmonic hot spots along the z-axis. This substrate detects even lower molecular concentrations, offering significant advancements for SERS-based applications [35,36].…”