Eighteen-month assessment of 3D graphene oxide aerogel-modified 3D graphite fiber brush electrode as a high-performance microbial fuel cell anode

The three dimensional (3D) carbonaceous materials with high surface area, conductivity, biocompatibility and stability are attractive for application in microbial fuel cells (MFCs), because they can facilitate extracellular electron transfer (EET) and enhance power performance. Here we prepare a 3D-3D structured anode composed of graphite fiber brush (GFB) modified with graphene oxide aerogel (GOA) and evaluate its performance during 18-month incubation. The long-racellular electron transfer (EET) and enhance power performance. Here we prepare a 3D-3D structured anode composed of graphite fiber brush (GFB) modified with graphene oxide aerogel (GOA) and evaluate its performance during 18-month incubation. The long-term operation yields a continuous enhancement of power generation, with 53.8 +/- 6.0 W m(-3) (normalized to anode chamber volume) achieved after 18 months. To our knowledge, this is the highest value obtained up to date for the similar dual-chamber MFCs with ferricyanide in the cathode. The results obtained from 18-month assessment on the GOA-GFB bioanode confirm the increased EET kinetics with successive operation. This increment can be explained by the facts that the 3D-3D structure with a high specific surface area is beneficial to bacteria growth, and that the in-situ formed microbially reduced GO is efficiently interacted with the electrochemically active bacteria. Our findings suggest that the 3D-3D GOA-GFB is a high-performance MFC anode that can sustain the long-term enhancement in performance. (C) 2016 Elsevier Ltd. All rights reserved.