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Abstract Existing pathways to produce graphite which include extraction of natural graphite impact the environment, while the conversion of fossil-driven carbon to graphite around temperatures as high as 3000 °C consumes large quantities of energy. Potassium - catalyzed graphitization is a more sustainable route and can achieve graphitic carbon formation at temperatures lower than 1000 °C, while enhancing pore formation and creating porous graphitic carbon (PGC). This two-step approach involves carbonization followed by graphitization. However, the compositions of the gaseous products have not been reported in prior studies. In this perspective, the chemical transformations underlying Alkaline Thermal Graphitization (ATG) for the co-production of synthesis gas (H2and CO) and PGC in a single step, utilizing lignocellulosic biomass, are reported. The presence of graphitic and porous carbon structures in PGC are well suited for supercapacitor applications. This promising approach maximizes resource recovery by upgrading volatile matter to synthesis gas and low value biomass residues to porous graphitic carbon (PGC), thus co-producing sustainable fuels and energy storage materials, while lowering CO2emissions compared to existing pathways to produce graphite.
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Solution-processable porous graphitic carbon from bottom-up synthesis and low-temperature graphitization
It is urgently desired yet challenging to synthesize porous graphitic carbon (PGC) in a bottom-up manner while circumventing the need for high-temperature pyrolysis. Here we present an effective and scalable strategy to synthesize PGC through acid-mediated aldol triple condensation followed by low-temperature graphitization. The deliberate structural design enables its graphitization in situ in solution and at low pyrolysis temperature. The resulting material features ultramicroporosity characterized by a sharp pore size distribution. In addition, the pristine homogeneous composition of the reaction mixture allows for solution-processability of the material for further characterization and applications. Thin films of this PGC exhibit several orders of magnitude higher electrical conductivity compared to analogous control materials that are carbonized at the same temperatures. The integration of low-temperature graphitization and solution-processability not only allows for an energy-efficient method for the production and fabrication of PGC, but also paves the way for its wider employment in applications such as electrocatalysis, sensing, and energy storage.
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- Award ID(s):
- 1851936
- PAR ID:
- 10315393
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 12
- Issue:
- 24
- ISSN:
- 2041-6520
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d1sc01902c
