Innovative technologies such as fuel and solar cells, supercapacitors, batteries, sensors, electrochemical energy storage devices are some of the most studied solutions to future energy demands due to an exponential population increase, estimated to reach over nine billion by 2050. [1] In fuel cells, chemical energy is directly converted to electricity. This fact is the main driving force through high-performance electrodes with improved catalytic activities toward hydrogen oxidation reaction (HOR) or oxygen reduction reaction (ORR). The final performance of a microbial fuel cell (MFC) will depend on the following parameters: 1) the power at the output, 2) the current density, and 3) the Coulombic efficiency, [1,2] which in turn depend on several factors such as the conductivity and porosity of the anode, the type of proton exchange membrane used to separate the cell chambers, the type of organic substrate used in the oxidation reaction at the anode, as well as the ORR at the cathode. However, the cathodic ORR in many cases has proven to be a limiting factor in the total energy generation in the cells, hence considered as one of the greatest performance indicators of a microbial fuel cell. [2] The commercial Pt/C catalyst is the common reference because of its great performance towards ORR with a limiting current density around 6 mA cm À2 at 0.7 V versus RHE (reversible hydrogen electrode) and 1600 rpm. Catalysts such as phosphorus doped hierarchical porous carbon showed a shift of around 70 mV for the onset potential compared with the Pt/C electrode. [3] Carbon fiber paper with Pt 3 Co showing a limiting current density of 25.8 mA cm À2 at 0.2 V versus RHE and 2500 rpm [4] and nanocomposites based on hybrid Mn 3 O 4 and oxidized graphene flakes provide a limiting current density of 2.8 mA cm À2 at À0.6 V and 1600 rpm. [5,6] Despite being the material with the highest electrocatalytic activity for ORR reported so far, Pt presents certain disadvantages like its high cost, toxicity, chemical instability, and biofouling, which still limit a widespread application. [7,8] These are the principal driving forces to find affordable materials to compete with Pt for ORR. Other metals such as copper, cobalt, or iron have been also reported as good candidates to replace the expensive Pt electrodes. Those materials exhibited currents, durability, and tolerance comparable with Pt, however, their ecological impact is highly