Nanotechnology for Wastewater Treatment and Bioenergy Generation in Microbial Fuel Cells

Abstract

Microbial fuel cells (MFCs) are bioelectrochemical systems that use bacterial metabolism to directly transform chemical energy into electricity. The microorganisms present in the anode chamber oxidize the organic matter present in a given substrate generating protons and electrons. While the electrons are externally led to the cathode to obtain an electrical current, protons migrate from the anode to the cathode normally through a separator and combine with electrons and oxygen to form water at the cathode. If wastewater is used as energy source, it can be treated while electricity is generated, obtaining a twofold benefit. The main components of these systems comprise anode and cathode electrodes, respectively, and a separator placed between them. During the last years, many electrode and separator materials, including physical and chemical modifications, have been studied in order to optimize this technology. Due to their advantageous properties, such as high catalytic activity and large specific surface, nanomaterials have been widely investigated in the main components of these systems. Thus, this chapter focuses on the recent advances related to the use of nanotechnology for the enhancement of the performance of MFC devices in terms of bioenergy production and wastewater treatment.