Facile and Scalable Synthesis of Whiskered Gold Nanosheets for Stretchable, Conductive, and Biocompatible Nanocomposites

Noble metal nanomaterials have been studied as conductive fillers for stretchable, conductive, and biocompatible nanocomposites. However, their performance as conductive filler materials is far from ideal because of their high percolation threshold and low intrinsic conductivity. Moreover, the difficulty in large-scale production is another critical hurdle in their practical applications. Here we report a method for the facile and scalable synthesis of whiskered gold nanosheets (WAuNSs) for stretchable, conductive, and biocompatible nano composites and their application to stretchable bioelectrodes. W-AuNSs show a lower percolation threshold (1.56 vol %) than those of gold nanoparticles (5.02 vol %) and gold nanosheets (2.74 vol %), which enables the fabrication of W-AuNS-based stretchable nanocomposites with superior conductivity and high stretchability. Addition of platinum-coated W-AuNSs (WAuNSs@Pt) to the prepared nanocomposite significantly reduces the impedance and improved charge storage capacity. Such enhanced performance of the stretchable nanocomposite enables us to fabricate stretchable bioelectrodes whose performance is demonstrated through animal experiments including electrophysiological recording and electrical stimulation in vivo.

Automated summary

This study reports a facile and scalable method for the synthesis of whiskered gold nanosheets (WAuNSs) that serve as conductive fillers for stretchable, conductive, and biocompatible nanocomposites. The addition of platinum-coated WAuNSs significantly improves the performance of the nanocomposites, enabling the fabrication of stretchable bioelectrodes.