Nanoadditives for Enzymatic Biohydrogen Production

Abstract

Using nanoadditives in biohydrogen production can be considered an optimal solution for existing challenges. Nanoparticles (NPs), affect the growth of microorganisms, intracellular electron transfers and the activity of metalloenzymes. The main research gap is to analyze and evaluate the effect of different types of NPs in several studies. The primary purpose of this study is to cover the research gap, by exploring the research databases, employing a complete list of search items followed by PRISMA guidelines. The taxonomy of the present study can cover these weaknesses and can successfully complement other studies. Evaluations have been conducted by the findings of the identified articles during the PRISMA guidelines. We also applied a feature selection technique to find the most important factor affecting the biohydrogen production yield. Accordingly, the additive values with the Relief feature selection score of 0.47±0.17 provided the highest impact on the biohydrogen production yield, followed by PH, with a score of 0.36±0.13. Finally, results showed that Fe-based additives boosted the catalytic mechanisms and metabolisms in all of the substrates. Conversely, Carbon-based additives enhanced glucose degradation in the substrates, and Biochar improved biological activity. The type of substrates and the number of NPs in each substrate are different. This study presents comparable results for each finding, based on the evidence. The main findings of this review can be of valuable help in the initial development of integrated additives, with different mechanisms of action.