Enhancing contact electrification using nanofluids during liquid intrusion and extrusion in nanoporous materials

Solid-liquid triboelectrification is of paramount importance for a wide range of processes. In this study, we demonstrate that a small addition of nanoparticles into water significantly enhances contact electrification in both intrusion–extrusion and immersion–emersion processes. In particular, fullerenol nanoparticles were applied as an aqueous nanofluid to intrusion–extrusion triboelectric nanogenerators. The results demonstrated more than one order of magnitude increase in energy output during intrusion–extrusion using two nanoporous materials with distinct porosities, mesoporous silica WC8 and the microporous MOF ZIF-8. These results suggest that even a minor presence of solid particles in a liquid plays a significant role in the process of solid-liquid contact electrification. This paves the way for efficient solid-liquid triboelectric generators based on nanofluids instead of simple liquids.