Performance of Perovskite-Type Oxides for Oxygen Reduction Reaction in Direct Hydrazine Fuel Cell. Issue 16 (26th November 2020)

• Record Type: Journal Article
• Authors: Nagai, Tsukasa; Kojima, Toshikatsu; Takeichi, Nobuhiko; Asahi, Masafumi; Yamazaki, Shin-ichi; Siroma, Zyun; Fujiwara, Naoko; Ioroi, Tsutomu
• Is Part Of: Journal of the Electrochemical Society. Volume 167:Issue 16(2020)
• Publication Date: 2020-11-26
• Subjects: Perovskite -- Direct fuel cell -- Anion exchange membrane -- Hydrazine -- Oxygen reduction reaction (ORR); Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/1945-7111/abc76d
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Perovskite-type oxide-based La0.6 Sr0.4 Mn(1- x ) Co x O3 /carbon ( x = 0, 0.1, 0.2, 0.3, 1) catalysts were prepared by calcination of a mixture of metal nitrates and PVP at 600 °C, followed by milling of the calcined powder with a carbon support. The catalytic activities for the oxygen reduction reaction (ORR) were tested in alkaline electrolyte by using a rotating ring-disk electrode (RRDE) at 25 °C. With an increase in the doping amount of Co, the onset potential of the La0.6 Sr0.4 Mn(1- x ) Co x O3 /carbon catalyst was found to be shifted in a positive direction and the ring current during ORR decreased. Especially, the La0.6 Sr0.4 Mn0.7 Co0.3 O3 /carbon ( x = 0.3) catalyst showed the highest ORR activity among the prepared catalysts. The La0.6 Sr0.4 Mn0.7 Co0.3 O3 /carbon was tested as the cathode of an alkaline membrane-type direct hydrazine fuel cell (DHFC), and a maximum power density of 133 mW cm −2, which exceeded that for the MEA using Pt/C (73.4 mW cm −2 ), was obtained at 50 °C. In addition, the open circuit voltage (OCV) for the DHFC (0.846 V) was greater than that of a commercial Pt/C cathode (0.788 V). Thus, the perovskite-type La0.6 Sr0.4 Mn0.7 Co0.3 O3 catalyst is expected to be a good candidate for use as a catalytic material for a DHFC cathode as an alternative to Pt.