Table 1. Experimental reaction rates α ₁ and α ₂ for R₁, R₂, S₁ and S₂ Janus particles calculated by fitting eqn (3) and (4) to the speed of the micromotors for 10% H₂O₂ concentration (Fig. S2, ESI). We used a = 1 Å and λ = 5 Å and solved for α ₁ and α ₂. We calculate the reaction rate k from eqn (4) at 10% H₂O₂ concentration to compare the surface reaction rate of the different micromotors (see S4, ESI for detailed discussion).

	α 1 (μm–2 s–1)	α 2 (μm–2 s–1)	k at 10% (μm–2 s–1)
R1	2.49 × 1010	1.6 × 1011	9.75 × 1010
R2	2.42 × 1010	6.40 × 1010	5.06 × 1010
S1	1.19 × 1011	2.57 × 1010	2.51 × 1010
S2	9.32 × 1010	2.50 × 1010	2.43 × 1010