fig3

Figure 3. Facet effect applied in Pd-based hydrides. (A) The structural model of intermediates; (B) diagram of ORR process energy profile on different Pd-H surfaces; (C) diagram of the optimized OH binding of twin-crystal Pd-H {111} surface (D) diagram of the moderate density of state on twin-crystal Pd-H {111} surface; (E) ORR polarization curves of various catalysts in 0.1 M KOH; (A-E) reproduced with permission from^[46]: Copyright 2021, Chinese Chemical Society.