The preparation of PANI-doped Co-Ni-ZIF carbonized derivatives and the exploration of EET process by the DFT calculation and the prediction of related functional genes

Abstract

As a green conversion/energy storage device, the practical application of microbial fuel cell (MFC) was limited with its low power generation. The extracellular electron transfer efficiency was one of the key factors affecting the power generation performance of MFC. This paper reported the carbonized derivative Co-Ni-ZIF@NC derived from PANI-doped Co-Ni-ZIF with conductivity, biocompatibility and high electrocatalytic activity. Density functional theory (DFT) confirmed the strong interaction between the electrode surface and microorganisms. The maximum power density of the MFC with Co-Ni-ZIF@NC anode (8.67 W/m3) was 1.47 time higher than that of Co-Ni-ZIF@C-800 (5.96 W/m3). High-throughput sequencing revealed that Co-Ni-ZIF@NC catalyst facilitated the screening of relevant functional microbial communities in microbial membranes, leading to the reinforcement of power generation in MFC. PICRUSt predicted the relative abundance of functional genes, confirmed the spontaneous enrichment behaviour of functional microorganisms to the electrode surface, and identified cytochrome c552 as the dominant role in the EET process. The above foregoing mainly due to the doping of PANI, improved the content of pyrrolic N on the surface of derivatives, protected the original crystal morphology, promoted the approaching behaviour of conductive flagella to the anode surface and shortened the electron transport distance, thus Co-Ni-ZIF@NC exhibited superb bioelectrocatalytic activity.