Flexible and luminescent fibers of a 1D Au(i)–thiophenolate coordination polymer and formation of gold nanoparticle-based composite materials for SERS

Abstract

Shaping of functional materials is of tremendous importance for applications. Among coordination polymer compounds, one of the challenges is to get fibers that can be self-standing and flexible, while maintaining their crystallinity and properties. Here, the synthesis and characterization of free-standing fibers of a Au(I)-based coordination polymer (CP) are reported. The flexible fibers of the 1D gold(I)–thiophenolate [Au(SPh)]_n CP have an average diameter of 270 nm and length of a few micrometers. They are hydrophobic because of the presence of phenyl rings and exhibit high chemical stability in harshly acidic and basic conditions due to the strong Au(I)–S interactions. These fibers are red-emissive at room temperature because of the presence of aurophilic interactions. In addition, a composite material can be easily obtained through calcination, resulting in the formation of gold nanoparticles (AuNPs) on the CP fiber surface. Owing to the plasmonic resonance of AuNPs, this composite material exhibits good sensitivity towards the detection of molecules as observed through surface enhanced Raman scattering (SERS).