Chemically activated graphite enhanced oxygen reduction and power output in catalyst-free microbial fuel cells. (1st March 2016)

• Record Type: Journal Article
• Authors: Zhang, Lehua; Lu, Zhihao; Li, DongMei; Ma, Jingxing; Song, Pengfei; Huang, Guangtuan; Liu, Yongdi; Cai, Lankun
• Is Part Of: Journal of cleaner production. Volume 115(2016:Mar.)
• Page Start: 332
• Page End: 336
• Publication Date: 2016-03-01
• Subjects: Activation -- Cathode -- Graphite -- Microbial fuel cell -- Oxygen reduction reaction; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2015.12.067
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: In search of a cost effective cathode material for microbial fuel cells (MFCs), graphite was chemically treated with H3 PO4, HNO3, ZnCl2, urea or melamine, and the effect of chemical activations on the oxygen reduction reaction (ORR) was examined. The performance of MFCs with activated graphite as the catalyst-free cathodes was then compared to those with untreated graphite. Results suggested that H3 PO4 and HNO3 activations could improved ORR, showing the highest ORR activity in graphite treated with 14.62 M H3 PO4 for 12 h at 30–50 °C. MFCs with H3 PO4 and HNO3 activated graphite cathodes generated maximum power densities (7.9 W/m 3 and 6.5 W/m 3, respectively) 2.4 and 1.8 times higher than that of the untreated control. The chemical activation process involves just a simple immersion step, and it does not require heating, electrochemical process or expensive chemicals. Therefore, it is a highly cost-effective approach to improve the performance of MFCs. We recommend an in-situ modification of graphite cathodes in scale-up MFCs with either H3 PO4 or HNO3 to optimize MFCs' various industrial applications. Highlights: Graphite activated by H3 PO4 or HNO3 has improved oxygen reduction potential. Power density of a cathode activated by H3 PO4 or HNO3 was higher than the control. Chemically activated graphite was used as the catalyst-free cathodes. Chemical activation is a cost-effective in-situ technology.