Surface patterning of <scp> GO‐ <i>S</i> </scp> / <scp>PLA</scp> nanocomposite with the assistance of an ionic surfactant for <scp>high‐performance</scp> triboelectric nanogenerator

Abstract

Porous graphene oxide-surfactant/poly(lactic acid) (GO-S/PLA) nanocomposite film with highly ordered hexagonal pore arrangement was fabricated via a combination of ionic interaction-supported GO dispersion and the improved phase separation method. First, a flat nanocomposite film is prepared by coating a well-dispersed GO-S/PLA solution on a solid substrate. Subsequently, the film is exposed to a mixture of chloroform and methanol as a suitable volatile solvent/nonsolvent pair for both PLA and surfactant-grafted GO sheets. A monolayer of honeycomb patterns is spontaneously formed on the nanocomposite surface after complete evaporation of liquids under normal air conditions. Methanol plays a crucial role in effectively inducing and controlling the ordered honeycomb structures. The pore array features, which include pore diameter and pore density, are tuned by adjusting methanol content. Moreover, the patterned GO-S/PLA nanocomposite demonstrates as an efficient electrification component for high-performance triboelectric nanogenerator (TENG) owing to a large surface area and abundant electron-donating groups of GO sheets. A new TENG is composed of the honeycomb GO-S/PLA (hc-GO-S/PLA) and its replica of microdome-patterned polydimethylsiloxane (md-PDMS), as a pair of tribo-components with antagonistic friction surfaces. As a result, it can generate an output power of 0.54 mW cm−2 which is 8.6 times higher than that of TENG with a flat surface and without GO additives. We believe that hc-GO-S/PLA nanocomposite has potential applications in biotechnology, optics, and catalyst fields.