title: Astronomical liquid mirrors as highly ultrasensitive, broadband-operational surface-enhanced Raman scattering-active substrates.
abstract: In this study, we found that an astronomical liquid mirror can be prepared as a highly ultrasensitive, low-cost, highly reproducible, broadband-operational surface-enhanced Raman scattering (SERS)-active substrate. Astronomical liquid mirrors are highly specularly reflective because of their perfectly dense-packed silver nanoparticles; they possess a large number and high density of hot spots that experience a very high intensity electric field, resulting in excellent SERS performance. When using the liquid mirror-based SERS-active substrate to detect 4-aminothiophenol (4-ATP), we obtained measured analytical enhancement factors (AEFs) of up to 2.7×10(12) and detection limits as low as 10(-15) M. We also found that the same liquid mirror could exhibit superior SERS capability at several distinct wavelengths (532, 632.8, and 785 nm). The presence of hot spots everywhere in the liquid mirror provided highly repeatable Raman signals from low concentrations of analytes. In addition, the astronomical liquid mirrors could be transferred readily onto cheap, flexible, and biodegradable substrates and still retain their excellent SERS performance, suggesting that they might find widespread applicability in various (bio)chemical detection fields.
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
authors.forename: Tai-Yen
authors.initials: TY
authors.lastname: Lu
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
authors.forename: Yang-Chun
authors.initials: YC
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
authors.forename: Yu-Ting
authors.initials: YT
authors.lastname: Yen
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
authors.forename: Chen-Chieh
authors.initials: CC
authors.lastname: Yu
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan. Electronic address: hsuenlichen@ntu.edu.tw.
authors.forename: Hsuen-Li
authors.initials: HL
authors.lastname: Chen
mesh_terms: D000814:Aniline Compounds / Q000032:analysis*; D001671:Biochemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013438:Sulfhydryl Compounds / Q000032:analysis*; D013499:Surface Properties
chemical_list: D000814:Aniline Compounds; D013438:Sulfhydryl Compounds; D012834:Silver; C064316:4-aminothiophenol
keywords: Astronomical liquid mirror; Broadband-operational; Hot spots everywhere; Surface-enhanced Raman scattering; Ultrasensitive