Synthesis, Modification, and Evaluation of MXene as a Novel Anode Electrode Material for Bio-electrochemical Systems

Bioelectrochemical systems (BESs) show promising prospects for recovering energy and chemicals from industrial and municipal wastewater. Despite the advances in the development of this technology, there is still a significant need for efficient electrode materials with high conductivity, hydrophilicity, and good biocompatibility to boost their performance and increase productivity. In this work, metal nanoparticle-two-dimensional MXene (W2N-Ti3C2Tx and Fe-W2N-Ti3C2Tx) composite electrocatalysts were synthesized using a simple impregnation method and deposited on carbon cloth (CC) to be used as a cheap and high performing anode in BESs. The plain CC, Ti3C2Tx-CC, W2N-Ti3C2Tx-CC, and Fe-W2N-Ti3C2Tx-CC were characterized using several techniques including scanning electron microscopy, transmission electron microscopy, water contact angle, and atomic force microscopy. The prepared anodes were tested in a single chamber air cathode microbial fuel cell inoculated with industrial wastewater for power generation and wastewater treatment simultaneously. The obtained results show that carbon cloth modified with W2N-Ti3C2Tx and Fe-W2N-Ti3C2Tx exhibited improved power density of 548 mW m-2 and 327 mW/m-2 with 81% and 44%, coulombic efficiency, respectively. The obtained power densities were 6 and 3.7 times higher, respectively than that achieved for pure carbon cloth (88 mW m-2). This study demonstrates the potential of combining two-dimensional MXene with metal nanoparticles to form an active composite anode catalyst for enhancing power generation and wastewater treatment using microbial fuel cells.