High-Performance Materials from Bio-based Feedstocks. Группа авторов

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High-Performance Materials from Bio-based Feedstocks - Группа авторов


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      2.3.4 Graphene Preparation from Biomass

      Graphite is an infinite three‐dimensional (3D) material comprising several stacked layers anchored by weak Van der Waals forces. Each stacked layer is a two‐dimensional (2D) carbon sheet structured in a hexagonal honeycomb lattice called graphene [65, 66]. Graphene was discovered in 2004 and presents astonishing properties. Its appearance is like a soft film, and it has a high Young’s modulus and excellent thermal and electrical properties. Previous research reveals that graphene has a very high surface area of over 2000 m2 g−1 and can be easily chemically modified [67]. Within the past decade, numerous investigations have used graphene in various applications along with exploring the practical synthesis procedures of graphene from biomass [68, 69]. Graphene can be synthesized through several methods including micromechanical exfoliation of graphite, chemical vapor deposition (CVD) of graphite, epitaxial graphene growth on silicon carbide, chemical graphitization of graphene oxide, and carbonization of biomass and waste materials [70–74]. Micromechanical exfoliation and CVD of graphite produced good‐quality graphene. The transformation of biomass into graphene can be accomplished via the carbonization of biomass under specific conditions. For example, pyrolysis of camphor leaves at an ultra‐high temperature of 1200 °C under nitrogen or argon atmosphere produced a biochar, which was subsequently reacted with D‐tyrosine as a bio‐based dispersion agent under sonication to obtain graphene [75]. The graphene derived from biomass contained many impurities, whereas the graphene synthesized from graphite is usually purer. To avoid contamination, some researchers used pure lignin to produce fine graphene through a stepwise pyrolysis process [76]. The biomass type may affect the properties of graphene as well. Populus wood was mixed with KOH before carbonization under nitrogen. Surprisingly, the graphene‐like carbon material was found on the structure of the obtained biochar [20]. Sucrose, xylitol, and glucose were also used as starting materials for graphene synthesis. The carbonization of sugar mixed with FeCl3 generated graphene‐like carbon materials, which presented excellent catalytic activity in the hydrogenation of nitrobenzene [77]. Even though graphene is one of the beneficial carbon materials, the production of graphene from biomass without any impurities remains a challenge.

Bio‐based carbon materials Surface area (m2 g−1) Pore volume (cm3 g−1) Functional groups
Biochar 100–500 0.03–0.25 –COOH, –OH, C–H, C=C, C=O
Hydrochar 1–43 0.007–0.2 –OH, C=C, C=O, C–C, –CH2, –CH3
Activated carbon (chemical treatment) 400–2700 0.3–1.53 –OH, C–H, C=C, C–O
Activated carbon (physical treatment) 300–1000 0.1–0.99 –OH, C=O, C–O
Graphene 800–1800 0.3–0.9 C–H, C–OH, C=C
Sugar‐derived carbon 1–5
Carbon nanotube 300–600 2.5 –COOH, –OH

      Over 90% of chemical industries (e.g. petroleum, renewable energy, fine chemicals, polymers, and food and pharmaceutical industries) are associated with catalytic processes. In 2019, approximately


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