3D printing gradient porous graphene oxide three-dimensional microorganism electrode and preparing method thereof

Abstract

The invention provides a 3D printing gradient porous graphene oxide three-dimensional microorganism electrode and a preparing method thereof. According to the 3D printing gradient porous graphene oxide three-dimensional microorganism electrode, Fe3+ or Ca2+ is crosslinked with graphene oxide molecules, or graphene oxide hydrogel made of Fe3O4 or FeS2 conductive nanoparticles is further added for serving as the material, and the 3D printing technology is adopted for preparing. On the basis of the 3D printing principle of low-temperature deposition, the graphene oxide hydrogel serves as the printing material, the three-dimensional electrode with the gradient pore structure, good biocompatibility, good conductivity and good interface electronic transmission properties is manufactured, the electrode is applied to a microorganism electrochemistry system, and the electrochemistry efficiency is improved.

Description

technical field [0001] The invention belongs to the technical field of microbial electrochemical system electrode manufacturing in the field of renewable energy, and specifically relates to a three-dimensional microbial electrode with a gradient pore structure and a preparation method and application thereof. Background technique [0002] The microbial electrochemical system is a new type of energy conversion device, and its main feature is to use the electrochemically active bacteria attached to the electrode surface as a catalyst to drive the redox reaction of the electrode. Among them, microbial fuel cells generate current while degrading organic matter in wastewater, and microbial electrosynthesis systems can produce fuels or chemicals at a relatively small applied voltage (0.2V-0.8V). Microbial electrodes, as the core component of the performance of microbial electrochemical systems, are the key factors that determine the performance of microbial electrochemical systems...

AI Technical Summary

Problems solved by technology

[0005] Although the graphene structure has good electrical conductivity, graphene oxide hydrogel has higher viscosity at higher concentration, but there are still many problems in the process of using graphene oxide hydrogel to prepare three-dimensional electrodes: (1) The forming problem of graphene oxide hydrogel: Even at a higher concentration, the viscosity of graphene oxide hydrogel is not enough to support the three-dimensional porous structure of 3D printing, and the adhesion between filaments and the collapse of the overall structure are very easy to occur

(2) The forming accuracy of graphene oxide hydrogel: due to the certain elasticity of graphene oxide hydrogel, there are internal stress and large internal strain in the gel during the printing process, which makes the extrusion and The stop time cannot be precisely controlled, which greatly affects the forming accuracy of the material

(3) Conductivity of three-dimensional electrodes: graphene oxide itself is almost non-conductive, and graphene oxide needs to be reduced to graphene

However, the use of general hydroiodic acid reduction will make the electrode toxic and unsuitable for microbial growth

At the same time, the overlapping structure between graphene oxide sheets is not conducive to the effective retransmission of electrons.

(4) The problem of interfacial electron transfer between the microbial catalyst attached to the electrode surface and the electrode: the ability of microorganisms to obtain electrons from the electrode (or the ability of microorganisms to oxidize organic matter to generate electrons to the electrode surface) has a decisive impact on the performance of microbial electrochemical systems , however, in current microbial electrochemical systems, the interfacial electron transfer rate between microorganisms and electrodes is low

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