Novel graphene-supported bimetallic Pt-Ni, Au-Ni and Fe-Sn CN-electrocatalysts for the oxygen reduction reaction

(POSTER) One of the main drawbacks for the commercialization of the proton exchange membrane fuel cells (PEMFCs) and anion exchange membrane fuel cells (AEMFCs) is the sluggish kinetics of the oxygen reduction reaction (ORR). Up to now, carbon-supported Pt/C is the most efficient electrocatalyst (EC) for the ORR. Nonetheless, the low abundance of platinum and the insufficient durability of these ECs, which results from the degradation of the carbon support, constitute some of the major challenges for large-scale commercialization of PEMFC and AEMFC technology [1, 2].Thus, the development of very efficient cathodic electrocatalysts is primordial to substitute the current commercialized Pt/C. In this work, a new type of electrocatalysts for the ORR is synthesized, following an innovative preparation protocol [3]. The electrocatalysts consist of a carbon nitride (CN) matrix coordinating bimetallic Pt-Ni, Au-Ni and Fe-Sn nanoparticles; the carbon nitride matrix further coats graphene particles, which act as the support. In this way, a “core-shell” morphology is successfully prepared with a CN "shell" and a "core" made of graphene supported bimetallic nanoparticles [4]. The chemical composition of the electrocatalysts is investigated by inductively-coupled plasma atomic emission spectroscopy (ICP-AES) and microanalysis; the morphology is characterized by high-resolution scanning electron microscopy (HR-SEM) and high-resolution transmission electron microscopy (HR-TEM). The structure of the electrocatalysts is studied by powder X-ray diffraction (XRD). Finally, the performance of the electrocatalysts for the ORR and the reaction mechanism are determined by cyclic voltammetry with the thin-film rotating ring-disk electrode (CV-TF-RRDE) technique (Figure 1). REFERENCES [1] R. Othman, A. L. Dicks, Z. Zhu, Int. J. Hydrogen Energy 37, 357 (2012). [2] S. Zhang, X.-Z. Yuan, J. N. C. Hin, H. Wang, K.A. Friedrich, M. Schultze, J. Power Sources 194, 588 (2009). [3] V. Di Noto, E. Negro, F. Bertasi et al., Patent application 102015000055603. [4] V. Di Noto, E. Negro, S. Polizzi et al., ChemSusChem. 5, 2451 (2012).