fig7

From: Tribocatalysis: evolution toward efficient heterogeneous catalysis in aqueous solutions

Figure 7. Comparison of H₂ production after 1 h magnetic stirring for several friction pairs. A PTFE magnetic rod rotating at 1500 rpm was used for NiO/glass and Co₃O₄/glass, whereas a PTFE magnetic rotary disk rotating at 400 rpm was used for Co₃O₄/glass, Co₃O₄/Ti, and Al₂O₃/Si. Reprinted with permission from^[61]. Adhering to the CC BY 4.0 agreement. PTFE: Polytetrafluoroethylene.