Single-Atom-Based Tandem Catalyst Superparticles to Form Stable Nanostructures

Stabilizes Catalytic Sites in a Controlled Hierarchical Structure

This catalyst production system can construct highly stable superstructures with total-length-scale controlled, catalytically active, single-atom sites usable in a tandem-catalyst system. Single-atom catalysts (SAC) display higher rates of selectivity than their conventional bulk chemical counterparts, helping catalyze only one particular reaction or yield a particular product. However, currently used single-atom-catalyst systems suffer from low volumetric density and uncontrolled spatial organization, reducing their overall effectiveness in certain chemical reactions.

Researchers at the University of Florida have developed a total-length-scale controlled production system that synthesizes high-integrity catalyst superstructures. Creating a composite superstructure system using single-atom nanoparticles improves heat resistance and catalyst stability.

Application

Production system creating single-atom-catalyst nanoparticle-based superstructures with controlled porosity and position

Advantages

• Controls porosity and position of component nanoparticles, improving thermal stability, volume density, spatial organization and substrate selectivity
• 3D prints macroscopic catalyst pallets using superparticle inks made from self-assembly of single-atom-catalyst-modified nanoparticles, achieving the total-length-scale control of catalytic sites in three dimensions: from the atomic scale to nanometer scale, to micrometer scale, and to macroscopic scale
• Increases control over overall catalyst reaction system, potentially optimizing reaction selectivity and yield rates in chemical coupling interactions

Technology

Spherical single-atom catalyst nanoparticles form through core synthesis and subsequent surface doping with catalytically active elements. Once these particles are chemically activated at their activity sites, the process creates nanoparticles which remain stable when subject to high temperatures. Dodecyl trimethylammonium bromide then renders created nanoparticles with hydrophobic ligands less reactive, forming an aggregate of nanoparticles in aqueous solution. When stirred and mixed with ethylene glycol, the solution degrades and superparticles begin to self-assemble from nanoparticles. 3D printing of previously created superparticles prompts their arrangement into catalytic superstructure systems and permits structural control at the sub-micron level. These formed superstructures can then potentially be used as tandem catalysts in coupling reactions, such as the conversion of basic hydrocarbons to value-added chemicals.