Pt-Free Metal Nanocatalysts for the Oxygen Reduction Reaction Combining Experiment and Theory: An Overview.

Heriberto Cruz-Martínez,Wilbert Guerra-Cabrera,Yesica A Peña-Castañeda,Hugo Rojas-Chávez,Dora I Medina,Ernesto Flores-Rojas,Dunia Ruiz-Villalobos

doi:10.3390/molecules26216689

Abstract

The design and manufacture of highly efficient nanocatalysts for the oxygen reduction reaction (ORR) is key to achieve the massive use of proton exchange membrane fuel cells. Up to date, Pt nanocatalysts are widely used for the ORR, but they have various disadvantages such as high cost, limited activity and partial stability. Therefore, different strategies have been implemented to eliminate or reduce the use of Pt in the nanocatalysts for the ORR. Among these, Pt-free metal nanocatalysts have received considerable relevance due to their good catalytic activity and slightly lower cost with respect to Pt. Consequently, nowadays, there are outstanding advances in the design of novel Pt-free metal nanocatalysts for the ORR. In this direction, combining experimental findings and theoretical insights is a low-cost methodology—in terms of both computational cost and laboratory resources—for the design of Pt-free metal nanocatalysts for the ORR in acid media. Therefore, coupled experimental and theoretical investigations are revised and discussed in detail in this review article.

Highlights

The proton exchange membrane fuel cells (PEMFCs) are electrochemical devices that have gained great importance because they directly convert the H2 chemical energy into electric energy. Such energy conversion occurs through two half reactions, namely the hydrogen oxidation reaction (HOR) and the oxygen reduction reaction (ORR) [1,2,3,4]
The ORR limits the overall performance of the PEMFCs
Based on theoretical and experimental evidence, the enhanced ORR catalytic activity could be attributed to the decrease of the adsorption energy of the reaction intermediates on B-doped Pd nanocatalyst compared with Pd nanocatalyst [49]

Summary

Introduction

The proton exchange membrane fuel cells (PEMFCs) are electrochemical devices that have gained great importance because they directly convert the H2 chemical energy into electric energy. For the theoretical studies of ORR nanocatalysts, different catalytic activity predictors have been proposed, such as ORR intermediates’ adsorption energies, d-band center and free-energy diagrams of the ORR [38,39], which have shown good agreement with the experimental results.

Results

Conclusion