Design a promising non-precious electro-catalyst for reduction reaction in fuel cells

We utilized quantum-chemical computations for computing the thermodynamic varia-tions in the Gibbs free energy of the potential reaction steps in the oxygen reduction re-action (ORR) of the nickel-and nitrogen-doped graphene (NiN3-Gr) catalyst's active center. We observed the consistency of the energies of adsorption for all O-containing in-termediates. The great thermodynamic driving forces (or motives) for reducing OOH into 2OH* or O* and the minor motives for generating H2O2 show the advantageousness of following a 4-electron pathway compared to a 2-electron one. This reaction's rate -determining step has 0.94 eV energy barrier that is associated with the first H2O mole-cule formation. According to the thermodynamics results, at lower than 0.51 V electrode potential by the 4e- pathway, the elementary steps of ORR are downhill. The last step, which is the OH reduction into H2O with the largest value of DG, acts as the 4e- pathway's thermodynamic RDS. Experimental scientists can use the theoretical results achieved in the current study in order to synthesize and select appropriate combinations of NiN3-Gr for applications in fuel cells. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.