Synthesis and formation mechanisms of biomass-derived carbonaceous materials are critically reviewed in terms of biomass sources, conversion methods and additives for energy and environmental applications.
The transformation of biomass to carbonaceous materials has recently attracted increasing attention because of its high carbon content and renewable nature. Various applications of biomass-derived carbonaceous materials are currently sought because of their potential cost-effective, large-scale, and quality-controllable production in an eco-friendly manner. In comparison to traditional synthesis of biomass-derived hydrochars, biochars, activated carbon and carbon fibers, the transformation of biomass to carbon nanomaterials exhibits attractive potential for biomass valorization. This critical review compares the various biomass-derived carbonaceous materials, highlighting the development of carbon nanomaterials ( e.g., graphene quantum dots, carbon nanotubes and graphene) from biomass. The merits and limitations of various synthesis methods are discussed for developing high-quality carbonaceous materials. The roles of biomass precursors, conversion methods and additives with desired characteristics are delineated. Insights into mechanisms involved in the conversion of biomass to carbonaceous materials are provided for each specific type of biomass precursor. Emerging energy and environmental applications of biomass-derived carbonaceous materials are summarized based on their specific physicochemical properties. This review concludes with an overview of current knowledge gaps and proposes future research directions for advancing the large-scale production of biomass-derived carbonaceous materials for attractive and practical applications in the fields of energy and environment.