Recent Advances in Microbial Electrolysis Cells for High Production of Hydrogen

The generation of hydrogen gas through microbial electrolysis (MEC), which is one of the bioelectrochemical system (BES) approaches, has been extensively explored in recent years. The biohydrogen produced in this process is considered green hydrogen and thus is an alternative to other conventional methods that mostly produce blue or gray hydrogen which is unsustainable. MEC harnesses electrogenic microbes, which can metabolize organic matter and generate electricity to drive the recombination of protons to hydrogen gas, which can metabolize organic matter and generate electricity to drive the recombination of protons to hydrogen gas. Albeit its’ potential as a green technology for green fuel synthesis, the process is still far from realization, mainly due to the low productivity and the low rate of reaction which is still low. Plus, the feasibility of MEC on a large scale is challenging because expensive electrode catalysts usually consist of noble metals. However, recent revelations and breakthroughs have provided insight into the accelerating potential of MEC in terms of electrode materials, system configurations, microbiology aspects of the microbes used, modeling, and recent scale-up attempts at MEC that have shown promising results. This review will discuss recent achievements relating to the MEC system and highlight future recommendations.