Pt Single Atom and Atomic Cluster-Enhanced TiO2 Janus Micromotors for Efficient Bubble Propulsion and Photocatalytic Environmental Remediation

Abstract

Bubble-propelled catalytic micro-/nanomotors, known for their strong thrust, rapid speeds, and long lifespan independent of ionic strength, have attracted significant attention. Despite significant advances in single-atom catalysis for its remarkable catalytic efficiency, single-atom catalysts alone generally lack sufficient activity to decompose hydrogen peroxide (H₂O₂) efficiently, limiting their applicability in bubble-propelled micro-/nanomotors for environmental use. Herein, we report a novel approach for fabricating Pt-decorated titanium dioxide micro-bowls (Pt_SA&C-TiO₂) featuring dual active sites with atomically dispersed Pt single atoms (SAs) and atomic clusters (Cs). This design significantly enhances the propulsion capabilities of Janus micromotors, allowing the Pt_SA&C-TiO₂ Janus micromotors to reach a speed of 113 ± 47 μm/s by decomposing H₂O₂ in aqueous solution, benefiting from the metallic characteristics of atomic clusters. Additionally, Pt_SA&C-TiO₂ Janus micromotors exhibit superior photocatalytic performance in pollutant degradation, demonstrating promising potential for environmental remediation. Finally, we investigated the effects of temperature and solute transport on the self-assembly of Janus TiO₂ micro-bowls, demonstrating the morphology’s controllability, which supports scalable production of these micromotors. This study not only highlights the potential of Pt_SA&C-TiO₂ Janus micromotors for environmental applications but also offers new insights into the design and application of single-atom-based micromotors.