Photo-induced surface-enhanced Raman spectroscopy from a diphenylalanine peptide nanotube-metal nanoparticle template

Abstract

UV irradiation of aligned diphenylalanine peptide nanotubes (FF-PNTs) decorated with plasmonic silver nanoparticles (Ag NPs) enables photo-induced surface-enhanced Raman spectroscopy. UV-induced charge transfer facilitates a chemical enhancement that provides up to a 10-fold increase in surface-enhanced Raman intensity and allows the detection of a wide range of small molecules and low Raman cross-section molecules at concentrations as low as 10–13 M. The aligned FF-PNT/Ag NP template further prevents photodegradation of the molecules under investigation. Our results demonstrate that FF-PNTs can be used as an alternative material to semiconductors such as titanium dioxide for photo-induced surface-enhanced Raman spectroscopy applications.

Three‐Dimensional TiO2−Ag Nanopore Arrays for Powerful Photoinduced Enhanced Raman Spectroscopy (PIERS) and Versatile Detection of Toxic Organics

“…Accordingly, 8‐fold increase of PIERS intensity was achieved under UV irradiation compared to that of non‐irradiated substrates. The results indicate that UV light irradiation is responsible for the enhancement of the PIERS signal of CV, which agrees well with the reported PIERS phenomena ,. To investigate the origin of PIERS effect, the UV‐vis absorption spectra of TiO 2 −Ag hybrid nanopore and pure Ag nanoparticles solution before and after UV irradiation were measured.…”

“…They proposed that the PIERS enhancement comes from the ultraviolet light induced charge migration from the semiconductor substrate to the metallic nanoparticles. Another exciting work also showed the PIERS based on diphenylalanie peptide nanotubes/Ag NPs template, which also achieved the same order chemical enhancement due to UV‐induced charge transfer. In addition to an improved Raman enhancement effects, these semiconductor‐plasmonic metal hybrid nanostructures are also employed to initiate plasmonic catalytic reactions due to their high efficient photocatalytic degradation and self‐cleaning ability under light irradiation …”

Efficient NIR energy conversion of plasmonic silver nanostructures fabricated with the laser-assisted synthetic approach for endodontic applications

“…However, this process is carried out at a higher temperature close to 100 C. The stabilizing effect of the citrate species relies on their immediate adsorption on the particle surface and provides strong electrostatic stabilization, preventing the subsequent aggregation of Ag-NPs. In accordance to Almohammed and Agnihotri, 24,25 the silver nuclei (with size up to 1 nm) appear immediately at the initial moment of irradiation during the photoinduced recovery in an aqueous medium. The nuclei coalesce into particle clusters spontaneously, and further growth of nanostructures occurs as a result of the reduction of silver ions on the surface of the Ag clusters (seed-mediated growth).…”

Photo-induced enhanced Raman spectroscopy (PIERS): sensing atomic-defects, explosives and biomolecules

“…The process was termed "Photo-induced enhanced Raman Spectroscopy", PIERS. Utilizing PIERS as an additional enhancement mechanism for trace level detection, additional studies on both traditional semiconductors 15,16 and un-conventional SERS substrates 17 have since been reported. Although within PIERS, resonant vibronic-coupling charge transfers are utilized, hence, a metal-free system would still facilitate semiconductordefect-analyte transfers with a noticeable PIERS enhancement.…”