Expanding the gallery of solvent-free nanofluids: Using layered double hydroxides as core nanostructures

Solvent-free nanofluids (SFNs), as an emerging category of materials, have shown significant potential in various fields. However, SFNs based on two-dimensional (2D) materials are rarely reported and have not been fully explored till now. Herein, we have demonstrated a general technique to convert layered double hydroxides (LDHs) into a new type of steady, homogeneous solvent-free LDHs nanofluids (LDH-F) by connecting corona-canopy species with LDHs nanosheets (LDH-NS) through the covalent bonding. As expected, LDH-F combined the fluidity with the functionality of the LDHs core nanostructure. The liquid-like properties enable LDH-F an excellent dispersion properties and the superior stability even after 100 days. To verify the universality of this method, different corona-canopy species and LDHs metal compositions were both investigated. As a proof concept, CO₂ selective sorption performance was investigated by both experimental and simulation methodologies. Remarkably, this work not only expands the gallery of SFNs, but also provides a universal approach to preparing 2D materials-based SFNs.