fig9
Figure 9. (A) HER polarization curves of NF, Mn3O4, PtSA-Mn3O4, and Pt/C. (B) The mass activity of Pt SA-Mn3O4 and Pt/C. (C and D) Calculated Gibbs free energy for the Volmer step on the surfaces, and GH* values of hydrogen evolution at the equilibrium potential of Mn3O4, Pt (111) and PtSA-Mn3O4[154]. (E) HER polarisation curves of Pt/C, Ru/C, and Ru-ZrO2-x/C catalysts. (F) Comparisons of the overpotentials at 10 mA cm-2. (G) Mass activities of Ru/C, Pt/C, and Ru-ZrO2-x/C catalysts and the hydrogen adsorption energies on the Ru(0001), Pt(111), and Ru-ZrO2-x surfaces obtained from DFT calculations[155].
