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 for applications in environmental remediation. While single-atom catalysts have demonstrated remarkable catalytic efficiency, their performance alone often lacks the necessary activity for efficient hydrogen peroxide (H₂O₂) decomposition, limiting their use in bubble-propelled systems. To address this, we present 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 capitalizes on the consistent metallic characteristics of Pt Cs, which significantly enhance the decomposition of H₂O₂ and propel the Janus micromotors to a speed of 113 ± 47 μm s⁻¹ in aqueous solutions. Furthermore, these Pt_SA&C-TiO₂ Janus micromotors exhibit excellent photocatalytic activity for pollutant degradation, which is enhanced by the synergistic effect of Pt SAs and Pt Cs. The study also discusses the factors influencing the self-assembly of Janus TiO₂ micro-bowls, emphasizing the simplicity and controllability of the fabrication process, which enables large-scale production. This work not only demonstrates 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.