A good though old introductory article based on Oak Ridge National Laboratory reasearch, that discusses the potential Graphite foam has with respect to heatsinks, and its limitations.

"There are other possible uses for foam heat sinks, as well. They may prove useful in protecting electronic components on space satellites from heat damage. Another possible application would be in evaporative cooling, in which the high specific surface area (>4m2/g) combines with the high thermal conductivity to produce very efficient cooling as water evaporates from the foam surfaces."