Novel self-supported reduced graphene oxide foam-based CoAu electrode: An original anode catalyst for electrooxidation of borohydride in borohydride fuel cell

• Published in: Carbon (New York) Vol. 152; pp. 77 - 88
• Main Authors: Li, Biaopeng, Song, Congying, Zhang, Dongming, Ye, Ke, Cheng, Kui, Zhu, Kai, Yan, Jun, Cao, Dianxue, Wang, Guiling
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 01.11.2019; Elsevier BV
• Subjects: Anodes; Borohydrides; Catalysts; Catalytic oxidation; Diffraction patterns; Electrodes; Fuel cells; Gold; Graphene; Hydrogen peroxide; Morphology; Nanoparticles; Organic chemistry; Oxidation; Photoelectrons
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2019.06.018

An original three-dimensional self-supported reduced graphene oxide (rGO) foam is successfully prepared in this work. This novel support material, modified with Co nanosheets and Au nanoparticles, is employed as a high-performance catalyst for NaBH4 electrooxidation under alkaline condition. The surface chemical component and morphology of the catalyst is characterized by X-ray diffraction pattern, X-ray photoelectron spectroscopy, scanning electron microscope. The synthesized electrode exhibits excellent performance (1.35 A cm−2 at 0 V) towards NaBH4 electrooxidation. The unique structure of rGO foam caused a large electrochemical active surface area (EASA(Au) = 390 m2 g−1), low electrochemical impedance, as well as 55.4% utilization efficiency of NaBH4. Also, catalytic kinetic parameters during the electrooxidation reaction of NaBH4 in a low NaBH4 concentration are investigated. Results indicate that oxidation of BH4− is a first-order reaction, and the exchanged number of electrons obtained at the CoAu/rGO foam electrode is 6.9. Finally, we practically apply it to a direct borohydride-hydrogen peroxide fuel cell (DBHPFC). This work suggests that the prepared rGO foam is an excellent current collector, and CoAu/rGO foam electrode is a promising anode catalyst to apply in DBHPFC. [Display omitted]