A REVIEW ON H2 PRODUCTION FROM PYROLYTIC BIOCHAR VIA ELECTROCHEMICAL OXIDATION

Increasing greenhouse gas emissions from the use of fossil fuels are causing climate change. Therefore, the use of sustainable and renewable energy sources as an alternative to fossil fuels has become a necessity rather than an option. Hydrogen (H2) is the most likely candidate fuel to replace hydrocarbon fuels as it will reduce greenhouse gas emissions. However, more than 90% of current H2 production comes from methane steam reforming or thermochemical methods that use fossil resources to produce H2. The electrolysis process is considered as an alternative to the existing hydrogen production methods as it allows the production of H2 from biomass waste. In this paper, studies on H2 production from pyrolytic biochar, a biomass by-product of the pyrolysis process, by electrochemical oxidation (such as biochar-assisted water electrolysis) were reviewed and the mechanism of electrochemical oxidation of pyrolytic biochar was elucidated. In addition, the effects of variables such as electrocatalyst, redox mediator, particle size, particle concentration on the electrochemical oxidation of pyrolytic biochar were explained. Finally, the challenges encountered in the electrochemical oxidation of pyrolytic biochar and the recommendations to overcome the related challenges were presented. Electrochemical oxidation of pyrolytic biochar is a research topic that has attracted attention in recent years. However, to the best of our knowledge, there is no review of studies on pyrolytic biochar-assisted water electrolysis in the existing literature. Therefore, it is believed that the results of this study will provide guidance to researchers or institutions wishing to work on the topic of pyrolytic biochar-assisted water electrolysis.