The effect of chemical vapor deposition temperature on the performance of binder-free sewage sludge-derived anodes in microbial fuel cells

Conversion of sewage sludge (SS) into value-added material has garnered increasing attention due to its potential applications. In this study, we propose a new application of the sewage sludge-derived carbon (SSC) as an electrode without binder in microbial fuel cells (MFCs). SS was firstly converted into SSC monoliths by methane chemical vapormethod at different temperature (600, 800, 1000 or 1200 degrees C). Scanning electron microscopy images showed that carbon micro-wireswere present on the surfaces of the samples prepared at 1000 and 1200 degrees C. The results showed that it was beneficial for converting sludge into a highly conductive electrode and increasing carbon content of the electrode at higher temperatures, thereby improving the current generation. The conductivity results show that a higher temperature favors the conversion of sludge into a highly conductive electrode. TheMFC using an SSC anode processed at 1200 degrees C generated the maximumpower density of 2228mWm(-2) and the maximum current density of 14.2 A m(-2). This value was 5 times greater than that generated by an MFC equipped with a graphite anode. These results present a promising means of converting SS into electrode materials. (C) 2018 Elsevier B.V. All rights reserved.