Nanostructured three-dimensional Reduced Graphene Oxide- Mn3O4?Architectures with High Conductivity and Bacteria Affinity for Highly Efficient Microbial Electrocatalysis

摘要

Bioelectrochemical system (BES) exhibits great potential for the wastewater treatment, which canachieve the energy storage simultaneously. However, the application of BES is limited due to the interiorstructure and composition of electrode materials. Here, a hybrid nano-structure reduced graphene oxideMn3O4 (rGO@Mn3O4) electrode was obtained through one-step electrodeposition method, and utilizedto enhance the performance of Geobacter sulfurreducens inoculated BES. The hierarchicalrGO@Mn3O4 is equipped with open porous and higher surface roughness, which are favorable for themicrobial colonization. And the electron transport from exoelectrogens to the electrode facilitated by thethree-dimensional interconnecting conductive scaffold. Further, the rGO@Mn3O4 electrode realized themaximum current density in a three-electrode setup reached 0.0376 mA cm?2 with high loading, whichis 3.03-fold higher than that of a bare rGO (0.0124 mA cm?2). The great performance is attributed to theproper pore size distribution and the “rose”-like porous structure Mn3O4 particles coating on the surfaceof the rGO sheets network. This work reveals a synergistic effect in pore structure and surface chemistrydesign to promote bioelectrocatalysis in BESs..