title: Improving SERS activity of inositol hexaphosphate capped silver nanoparticles: Fe3+ as a switcher.
abstract: Inositol hexaphosphate (IP6) capped silver nanoparticles (IP6@AgNPs) were fabricated as surface-enhanced Raman scattering (SERS) active substrates. SERS activity of IP6@AgNPs could be further improved via adding due amounts of Fe(3+) to form Fe(3+)-IP6@AgNPs. The mechanism of Fe(3+)-induced SERS improvement of IP6@AgNPs can be attributed to the strong interaction of IP6 and Fe(3+), which leads to controllable adjustment of the gap among neighboring nanoparticles to produce "hot spots". The above mechanism was confirmed with ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscope (TEM), dynamic light scattering (DLS), Fourier transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Such Fe(3+)-IP6@AgNPs-based SERS system was used to detect Rhodamine 6G (R6G) down to the trace level of 10(-10) mol L(-1). Besides, New Fuchsin (NF) was also used as a Raman probe to calculate the enhancement factor (EF) of IP6@AgNPs without and with Fe(3+). The SERS activity of IP6@AgNPs happened extreme decrease after one-year storage and could be recovered to great extent aided by the addition of Fe(3+). The Fe(3+) optimized IP6@AgNPs system could be applied to detect thymine at trace level by SERS.
authors.affiliation: Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University , 100 Guilin Road, Shanghai 200234, People's Republic of China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Guo
authors.forename: Yichen
authors.initials: Y
authors.lastname: Fu
authors.forename: Shuyue
authors.initials: S
authors.lastname: Fu
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Tianxi
authors.initials: T
authors.lastname: Yang
authors.forename: Ying
authors.initials: Y
authors.lastname: Wen
authors.forename: Haifeng
authors.initials: H
authors.lastname: Yang