Royal Society of Chemistry, Journal of Materials Chemistry C Materials for optical and electronic devices, 2(3), p. 399-408
DOI: 10.1039/c4tc01702a
Full text: Download
We examine the influence of confining gold nanoparticles on the overall nanoscale morphology, mechanical and electrochemical properties of the nanocomposite ion gels. Stimuli- responsive ion gels are generated via synthesis of gold nanoparticles (AuNPs) within thiol-functionalized liquid crystalline brush-like block copolymer (LCBBC) and subsequent gelation in ionic liquids. AuNPs are prepared by in situ reduction of the gold ions and stabilized by direct anchoring through the coordination bonds with the thiol-functionalized LCBBC. The resulting LCBBC/AuNPs nanocomposite comprise a hierarchical structure in which polymer-coated AuNPs are dispersed in a microsegregated LCBBC matrix that further contain both liquid crystalline (LC) and block copolymer ordering. More importantly, this LCBBC/AuNPs nanocomposite is solubilized in ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate, to form nanocomposite ion gel. At 5 wt% concentration, LCBBC/AuNPs nanocomposite ion-gel exhibits interesting characteristics including excellent mechanical strength (~ 103 Pa), good optical properties with higher ionic conductivity (~ 10-2 Scm-1) and long-term electrochemical stability over a larger potential range compared to plain LCBBC ion gel. Thus, nanocomposite ion gels present tunable optical, thermal and mechanical properties by virtue of their polymer architecture, morphology and functionality. These are versatile and modular hybrid materials to design nanocomposite ion gels with multiple functionalities for applications in electrochemical devices, photonics, and opto-electronics.