2D layered structure-supported imidazole-based metal-organic framework for enhancing the power generation performance of microbial fuel cells

Abstract

By self-assembly of imidazole-based ZIF67 in the two-dimensional (2D) MXene layer, A bio-compatible and bio-electrocatalytic anode combed of a metal organic framework (MOF) and MXene was created on the carbon felt by self-assembly of imidazole-based zeolite imidazolate framework-67 (ZIF67) in the 2D MXene layer. The maximum power density of the microbial fuel cells (MFCs) with Ti3C2-ZIF67/CF is 5.7 ± 0.12 W m−3 higher than that of Ti3C2/CF (4.07 ± 0.06 W m−3), ZIF67/CF (2.5 ± 0.04 W m−3) and CF (2.1 ± 0.1 W m−3). The charge transfer resistance of the composite anode (9.7 Ω) in the MFC is much lower than those of the Ti3C2 (15.3 Ω), ZIF67 (34.3 Ω) and CF (18.6 Ω) anodes. This enhancement was achieved because the composite combined the advantages of each component, including MXene's conductivity and hydrophilic and MOF's biocompatibility. Meanwhile, the composite anode accelerated the rate of the extracellular electron transfer (EET) between the anode and the microbes. Moreover, the high throughput sequencing technology reveals that the composite possessed good colonization of microorganisms and high biodiversity, with the microbial community playing an efficient synergistic role in facilitating electricity generation. Consequently, the Ti3C2-ZIF67 composite exhibited excellent bio-electrochemical performance as an anode material. This work not only expands the application of MXene in the bio-electrochemical system but also provides ideas for the development of MXene-based materials for MFCs.