Nanocarbon nanofluids: morphology and nanostructure comparisons.

Reported here are experimental results of studies designed to identify the operable mechanisms responsible for the gains in thermal conductivity of nanofluids based on nanocarbons. Comparison of functionalized versus nonfunctionalized nanocarbons addresses the effect of interfacial fluid ordering. Comparison between graphitized and nongraphitized carbon black addresses the effect of long-range phonon propagation. Comparison between multi-walled nanotubes and carbon black addresses particle aggregation by comparing two very different, yet fixed, nanocarbon morphologies. Lastly, partial network formation, i.e., spatially distributed clustering, is addressed by varied concentrations of different nanocarbon morphologies.