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> Once inside, the carbon assembles into a graphene-like sheet that lines the walls of the zeolite pores. In doing so, the surface stretches and bends negativel

> Once inside, the carbon assembles into a graphene-like sheet that lines the walls of the zeolite pores. In doing so, the surface stretches and bends negatively. I understand the negative curvature part, but the article fails to elaborate on why that’s an important or valuable property for a material to have. Can anyone explain a bit further?

jpfed 8y ago
This paper ( https://www.ncbi.nlm.nih.gov/pubmed/29141112 https://www.ncbi.nlm.nih.gov/pubmed/29141112 ) simulates schwartzite with a macroscopic 3d-printed model and finds that "these structures hold great promise as high load bearing and impact‐resistant materials due to a unique layered deformation mechanism that emerges in these architectures during loading.".
maxerickson 8y ago
Earlier in the article there is discussion about how there are positive folding and flat forms of carbon, leading chemists to search for a negative folding form. So I think it's not really implying anything more, just that they found one.
strainer 8y ago
It seems the curvature is positive or negative in relation to the overall body of the material. With positive surface curvature we get bubble or shell shaped objects which in bulk amount to a very fine powder. If those shells/balls are fused with each other into a regular lattice - most of the structure can be identical (except the fused parts) but the balls become connected holes in a larger rigidly connected body, which is formed by their union. Im guessing that in normal space negative curvature has to imply surfaces which do not bound a space, but which rather extend through a space - a kind of solid.
- lainga 8y ago
  Negative curvature means a saddle, right?
  - strainer 8y ago
    I see - like around the inside of a torus.
neltnerb 8y ago
Catalytic applications require finely tuned pore sizes and carbon may be more inert than the typical zeolite composition. Carbon is also probably electrically conductive, so it may be a basis for improved or different catalysts for fuel cells and battery electrodes. Just a first guess, and catalysts/batteries are an expertise so that's just where my mind goes first. I'm sure there are others.

jpfed 8y ago

This paper ( https://www.ncbi.nlm.nih.gov/pubmed/29141112 https://www.ncbi.nlm.nih.gov/pubmed/29141112 ) simulates schwartzite with a macroscopic 3d-printed model and finds that "these structures hold great promise as high load bearing and impact‐resistant materials due to a unique layered deformation mechanism that emerges in these architectures during loading.".

maxerickson 8y ago

Earlier in the article there is discussion about how there are positive folding and flat forms of carbon, leading chemists to search for a negative folding form. So I think it's not really implying anything more, just that they found one.

strainer 8y ago

It seems the curvature is positive or negative in relation to the overall body of the material. With positive surface curvature we get bubble or shell shaped objects which in bulk amount to a very fine powder. If those shells/balls are fused with each other into a regular lattice - most of the structure can be identical (except the fused parts) but the balls become connected holes in a larger rigidly connected body, which is formed by their union. Im guessing that in normal space negative curvature has to imply surfaces which do not bound a space, but which rather extend through a space - a kind of solid.

lainga 8y ago
Negative curvature means a saddle, right?
- strainer 8y ago
  I see - like around the inside of a torus.

neltnerb 8y ago

Catalytic applications require finely tuned pore sizes and carbon may be more inert than the typical zeolite composition. Carbon is also probably electrically conductive, so it may be a basis for improved or different catalysts for fuel cells and battery electrodes. Just a first guess, and catalysts/batteries are an expertise so that's just where my mind goes first. I'm sure there are others.