Nickel-cobalt oxide modified with reduced graphene oxide: Performance and degradation for energy storage applications

Alberto Adán-Más (1, 2) , Maria Teresa Silva (3, 1) , Liliane Guerlou-Demourgues (2, 4) , Lydie Bourgeois (5) , Chritine Labrugere-Sarroste (6) , Maria de Fátima Montemor (1)

1 CQE - Centro de Quimica Estrutural
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
3 ADEM, GI-MOSM, ISEL-Instituto Superior de Engenharia de Lisboa
4 RS2E - Réseau sur le stockage électrochimique de l'énergie
5 ISM - Institut des Sciences Moléculaires
6 PLACAMAT - Plateforme Aquitaine de Caractérisation des Matériaux

Nickel-cobalt oxide is synthesized in combination with electrochemically reduced graphene oxide (Er-GO) by one-step electrodeposition on stainless steel followed by thermal treatment. The presence of reduced graphene oxide leads to enhanced electrochemical response, with a capacity increase from 113 mA h g−1 to 180 mA h g−1, and to increased faradaic efficiency and rate capability. Compared to Ni-Co oxide, the addition of reduced graphene oxide increases capacity retention from 58% to 83% after 5000 cycles. The material fade during cycling is studied by means of electrochemical impedance spectroscopy, electron diffraction spectroscopy and scanning electron microscopy. As a result, different degradation mechanisms are identified as source of the capacity decay, such as microstructural cracking, phase transformation and parasitic reactions.

Mots clés: Electrochemically reduced graphene oxide; Nickel-cobalt oxide; Energy storage; Electrode degradation; Electrochemical impedance spectroscopy

Domaines: Matériaux

Alberto Adán-Más, Maria Teresa Silva, Liliane Guerlou-Demourgues, Lydie Bourgeois, Chritine Labrugere-Sarroste, et al.. Nickel-cobalt oxide modified with reduced graphene oxide: Performance and degradation for energy storage applications. Journal of Power Sources, 2019, 419, pp.12-26. ⟨10.1016/j.jpowsour.2019.02.055⟩. ⟨hal-02095664⟩