Synergic effects enhance the catalytic properties of alpha-Ni(OH)(2)-FeOCPc@rGO composite for oxygen evolution reaction

Author(s)

Goncalves, Josue M. ^[1] ; Matias, Tiago A. ^[1] ; Saravia, Lucas P. H. ^[1] ; Nakamura, Marcelo ^[1] ; Bernardes, Juliana S. ^[2] ; Bertotti, Mauro ^[1] ; Araki, Koiti ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Chem, Dept Fundamental Chem, Av Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil

^[2] Natl Ctr Energy & Mat CNPEM, Natl Nanotechnol Lab LNNano, Rua Giuseppe Maximo Scolfaro 10-000, BR-13083970 Campinas, SP - Brazil

• Document type: Journal article
• Source: Electrochimica Acta; v. 267, p. 161-169, MAR 20 2018.
• Web of Science Citations: 10

Abstract

The effect of size and degree of crystallinity, and the synergic interaction of alpha-Ni(OH)(2) nanoparticles (alpha-Ni) with reduced graphene oxide (rGO) and octacarboxyphthalocyaninate iron(II) (FeOCPc), on the electrocatalytic activity for the oxygen evolution reaction (OER) are demonstrated using structurally well-defined nanocomposite materials. Larger and crystalline alpha-Ni@ rGO-K nanoparticles (4.7 +/- 1.8 nm) generated materials with higher activity than the respective alpha-Ni(OH)(2)-Na derivatives (1.8 +/- 0.3 nm), where the incorporation of rGO improved dramatically the performance. However, an even larger efficiency was achieved when alpha-Ni@ rGO-K was covered up with a controlled amount of FeOCPc, a poor molecular OER catalyst, in this way demonstrating a synergic effect of that macrocycle on the reaction kinetics decreasing further the overpotential of the oxygen evolution reaction. In fact, alpha-NiFeOCPc@rGO-K was the ternary composite material with best performance, being able to sustain a stable current of 10 mA cm(-2) during 8 h of continuous electrolysis at 1.64 V vs RHE, in 1.0 mol dm(-3) KOH solution, showing good perspectives as electrode material for OER. (C) 2018 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 15/20776-9 - Fabrication of nanometric probes for the study of biochemical processes by using Scanning Electrochemical Microscopy
• Grantee: Mauro Bertotti
• Support Opportunities: Regular Research Grants