Nanoparticles Formed onto/into Halloysite Clay Tubules: Architectural Synthesis and Applications

Abstract

Nanoparticles, being objects with high surface area are prone to agglomeration. Immobilization onto solid supports is a promising method to increase their stability and it allows for scalable industrial applications, such as metal nanoparticles adsorbed to mesoporous ceramic carriers. Tubular nanoclay - halloysite - can be an efficient solid support, enabling the fast and practical architectural (inside / outside) synthesis of stable metal nanoparticles. The obtained halloysite-nanoparticle composites can be employed as advanced catalysts, ion-conducting membrane modifiers, inorganic pigments, and optical markers for biomedical studies. Here, we discuss the possibilities to synthesize halloysite decorated with metal, metal chalcogenide, and carbon nanoparticles, and to use these materials in various fields, especially in catalysis and petroleum refinery.

Development of Marine Antifouling Epoxy Coating Enhanced with Clay Nanotubes

“…Combination of silver nanoparticles with DCOIT loaded into an antifouling coating show synergetic effects against fouling [30]. Naturally excavated cheap halloysite nanotubes can be used as a container for DCOIT antifouling agent and serve as a template for Ag-particles formation preventing their undesirable aggregation [31][32][33][34].…”

Naturally derived nano- and micro-drug delivery vehicles: halloysite, vaterite and nanocellulose

“…and especially attractive for the entrapment of large macromolecules (genes, 25 enzymes 26 ) and nanoparticles (quantum dots, 27 metal nanoparticles, 28 more examples reviewed in ref. 29), whose sizes correlate well with the diameter of the lumen. Some recent reviews have described the loading of molecules and particles of various natures in more detail.…”

Ruthenium-Loaded Halloysite Nanotubes as Mesocatalysts for Fischer–Tropsch Synthesis

“…Recently, we showed that metal nanoparticles could be synthesized selectively inside halloysite using azines as complexing agents [17]. Ru loaded inside halloysite by complexation of RuCl 3 with 1,2-bis(2-furylmethylene)hydrazine was found to be efficient in the hydrogenation of mono-aromatics [18][19][20]. No works were performed on the complexing agent's effect on morphology, physico-chemical properties, and catalytic activity of ruthenium-loaded halloysite.…”