3D Printed Carbon Framework with the Graphene Aerogel for Microbial Fuel Cell Application

There is a high interest in living organism-compatible materials associated with electrically active interfaces. Bacteria/electrode interfaces implement smart, functional systems with responses, based on which it is possible to elaborate self-regulating energy generation systems. Carbon materials have a number of advantages, such as biocompatibility, low electrical resistance, and the possibility of increasing the electrode surface on an industrial scale. The most promising approach for the industrial production of electrodes is 3D printing. We propose a 3D-printed carbon electrode – a novel lightweight material for electrodes in bioelectrochemical systems for efficient bioelectricity utilization. The pyrolytic process for manufacturing carbon electrodes is promising for upscaling and industrial applications. However, there is a problem of volume loss when 3D-printed polymers are pyrolyzed in an inert environment. We propose a new strategy for the thermal treatment of 3D-printed polymers that allow for reduced volume loss under pyrolytic carbonization. In addition, to achieve a higher electrode surface area, the graphene aerogel could be impregnated into the 3D-printed scaffolds. Chemical modification of graphene surface can enhance biocompatibility. Specifically, the oxidation of graphene leads to forming a hydrophilic and biocompatible material. We tune graphene hydrophilic properties and electrical conductivity via control over the thermal reduction of the oxidized form of graphene–graphene oxide 1 . Such sponge morphology affords 3D-printed carbon scaffolds an excellent lightweight host scaffold for microorganisms, in which the graphene nanowalls are homogeneously occupied by S. oneidensis MR-1. We demonstrate a novel sustainable method to produce graphene-based lightweight 3D printed electrode materials for green energy production from biomass. The proposed technology creates the opportunity for novel, innovative, disruptive graphene applications that can lead to the establishment of new energy-related industries and facilitate many startups in the ecosystem. Acknowledgments This work was supported by the Ministry of Education (Singapore) through the Research Centre of Excellence program (grant EDUN C-33-18-279-V12, I-FIM). References Xuanye Leng, Ricardo J. Vazquez, Samantha R. McCuskey, Glenn Quek, Yude Su, Konstantin G. Nikolaev, Mariana C.F. Costa, Siyu Chen, Musen Chen, Kou Yang, Jinpei Zhao, Mo Lin, Zhaolong Chen, Guillermo C. Bazan, Kostya S. Novoselov, Daria V. Andreeva, Carbon, 205, 2023, 33-39.