Graphene production induced by negative thermal expansion
- Carbon buffer layer could be converted to graphene by rapid-cooling from 900 ºC to -196 ºC -
Researchers in Nagoya University succeeded to form freestanding graphene by dropping the carbon buffer layer sample heated at 900 ºC into liquid nitrogen. This is due to the physical breaking of atomic bonds between the buffer layer and SiC substrate, which is driven by the different thermal expansion coefficients of them. (Figure)
Graphenization of buffer layer by rapid-cooling
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