Figure 3.

Optimization of Fe thickness for efficient pollutant degradation using Fe/Pt micromotors. (A) Rhodamine 6G degradation over time with self-propelled micromotors containing different Fe thickness, i.e., from 20 to 200 nm, and constant Pt thickness at 1 nm. Each sample contained a 2 mL solution at pH 2.5 with Rh6G (C₀ = 100 mg/L), 5% H₂O₂, 1% SDS, and 882 ± 10 microtubes. The control sample was carried out under equal conditions omitting micromotors. Inset: Actively moving Fe/Pt micromotors in Rh6G solution. Scale bar: 250 μm. (B) SEM images of Fe tubes with 100 nm Fe thickness before Fenton reaction and (C) after 20 h of Fenton reaction. The blue triangles indicate the position of nanopits in tube walls.