Fig. 54. (a–c) HER activity of TMPs. (A) Linear sweep voltammograms (LVSs) per geometric area of representative TMP electrodes. The HER activity of Pt nanoparticles (NPs) is displayed for comparison. (d) Activity volcano for the HER showing the geometric current density from (A) at an overpotential of Z = 100 mV as a function of hydrogen adsorption free energy (DGH). (e) Activity volcano for the HER showing the ECSA normalised current density from (B) at Z = 100 mV as a function of DGH. (f) Activity volcano for the HER showing the average TOF from (C) at Z = 100 mV as a function of DGH. Reproduced with permission from ref. 928. Copyright RSC 2015.