Hydrogen gas (H2) is the primary storable fuel for pollution‐free energy production, with over 90 million tonnes used globally per year. More than 95% of H2is synthesized through metal‐catalyzed steam methane reforming that produces 11 tonnes of carbon dioxide (CO2) per tonne H2. “Green H2” from water electrolysis using renewable energy evolves no CO2, but costs 2–3× more, making it presently economically unviable. Here catalyst‐free conversion of waste plastic into clean H2along with high purity graphene is reported. The scalable procedure evolves no CO2when deconstructing polyolefins and produces H2in purities up to 94% at high mass yields. The sale of graphene byproduct at just 5% of its current value yields H2production at a negative cost. Life‐cycle assessment demonstrates a 39–84% reduction in emissions compared to other H2production methods, suggesting the flash H2process to be an economically viable, clean H2production route.
Responsible disposal of vehicles at the end of life is a pressing environmental concern. In particular, waste plastic forms the largest proportion of non-recycled waste material from light-duty vehicles, and often ends up in a landfill. Here we report the upcycling of depolluted, dismantled and shredded end-of-life waste plastic into flash graphene using flash Joule heating. The synthetic process requires no separation or sorting of plastics and uses no solvents or water. We demonstrate the practical value of the graphene as a re-inforcing agent in automotive polyurethane foam composite, where its introduction leads to improved tensile strength and low frequency noise absorption properties. We demonstrate process continuity by upcycling the resulting foam composite back into equal-quality flash graphene. A prospective cradle-to-gate life cycle assessment suggests that our method may afford lower cumulative energy demand and water use, and a decrease in global warming potential compared to traditional graphene synthesis methods.
more » « less- NSF-PAR ID:
- 10367515
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Communications Engineering
- Volume:
- 1
- Issue:
- 1
- ISSN:
- 2731-3395
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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