“The ability to master efficient carbon cycling and creative carbon chemistry will thus determine human fate in the 21st century, if even just elemental necessities of modern life are to be maintained. A carbon (coal or biomass)-based material can in principle be cheaper and more sustainable than the current petrochem- ical products, and carbon fixed in long- lasting materials is, from a different perspective, bound carbon dioxide taken out of the atmosphere, i.e., carbon- negative materials chemistry.”
Professor Markus Antonietti, in ADVANCED MATERIALS 22 (7). Carbon: the Sixth Element

Researching this field led me to Carbon Foam. The material consists of a stiff, porous structure formed from a web of carbon atoms. Previously used for applications such as aerospace tooling, fireproof wall core material, energy absorbing, blast protection and hot structures.

Carbon foams can be produced from a variety of different materials, including asphalt, foamed synthetic plastic, and coal. These starter materials help determine the properties the carbon foam will have. Foams derived from pitch conduct heat well and have low density, but are comparatively weak. Coal-based foams are stronger and denser but do not conduct heat as well. Lignin-based foams are strong yet lightweight, with low density and good thermal conductivity. Carbon foams are typically produced by decomposing the precursor in a closed vessel at high temperature under high pressure (hydrothermal carbonization).