Structure of research on biomass and bio-fuels: A citation-based approach

Biomass and bio-fuels have gained a growing interest as sustainable and renewable energy. In this paper, we perform a citation network analysis of scientific publications to know the current structure of biomass and bio-fuel research. By clustering and visualizing the network, we revealed their taxonomic structure. Emerging technologies are detected by analyzing the average publication year of clusters. According to the results, bio-diesel and hydrogen production are the most rapidly developing domains among biomass bio-fuel researches. We also analyzed the position of each cluster in the global structure of research. By using citation counts within and out of the cluster, we categorized each cluster into the following four categories: (I) topic specific; (II) domain specific; (III) global link; and (IV) specific & global. For research domains of category (III) or (IV), it is difficult that single technology overcomes the current limitation of bio-energy productions. Research on lignocellulose feedstock is a typical case where knowledge from other scientific disciplines is necessary.