Advances in hydrogen production from sustainable resources through biological and thermochemical pathways: Review and bibliometric analysis

The increasing concern about environmental degradation and an energy crisis due to geopolitical conflicts, economic sanctions, and worsened energy security has prompted energy researchers to find environmentally friendly and renewable sources as an alternative to fossil fuel sources. Hydrogen is one of the most suitable replacements for fossil fuels due to its good thermal properties, wide applicability, multiple sources, and being carbon-free. Hydrogen can be produced sustainably from different biomass sources through biological and thermochemical pathways. This manuscript aims to present a comprehensive analysis of current approaches for producing hydrogen from biomass sources, elucidating recent advancements in this domain. The manuscript outlines the benefits and drawbacks of different approaches. Furthermore, a thorough bibliometric analysis using VOSviewer software was carried out for the years 2000-2023, covering 1840 relevant references. The incorporation of an extensive bibliometric analysis enhances the scholarly depth of the research. Through the mapping of historical and contemporary research emphases, significant contributors, and emerging trends, the paper provides a precise visual depiction of the research landscape. This not only contributes to a nuanced comprehension of the field's present condition but also functions as a valuable instrument for researchers in strategizing future studies.