Influence of biomass addition on electricity harvesting from solid phase microbial fuel cells

• Difference on performance of SMFC with the added different biomass exists.
• Adding biomass can improve mass transfer limitation in the anode region.
• Adding biomass increased the organic matter content and enhanced cellulase activity.
• Added biomass to the matrix can generate more electricity during waste utilization.
• We report a simple and biomass accessed method for improving the performance of SMFC.

In this study, two types of biomass (Acorus calamus leaves and wheat straw) were added to a matrix of sediment and soil inside the anode of solid phase microbial fuel cells (SMFCs) in order to increase their output power. SMFC containing 3% leaves in their sediment had a maximum power density of 195 mW m−2 in contrast to 4.6 mW m−2 of that SMFC without leaves. Similarly, SMFC containing 1% wheat straw in their soil environment had a maximum power density of 167 mW m−2. It suggests that the addition of biomass in appropriate proportions increases contact opportunities between the matrix, the anode and the added biomass, increases organic matter content, and enhances cellulase activity, thus serving as an important method for enhancing output power in SMFCs.