Investigation of different nanoparticles for magnetophoretically enabled nanofin heat sinks in microfluidics

Abstract

Assembled nanofin heat sinks, nanostructures which are formed via external forces in a cooling microfluidic to remove heat from hot spots, are a new concept that has recently been introduced. In this work, we investigate nanofin structures formed by CrO₂ and Fe₂O₃ magnetic nanoparticles and compare their performance. Thermal imaging is used for comparison of three cases including: (i) DI water as the coolant liquid, (ii) suspension of magnetic particles in DI water, and (iii) suspension of magnetic particles in DI water in the presence of a magnetic field. For each case, the experiments are conducted at three different flow rates of 10, 40 and 120 μl min⁻¹. Our results suggest that the high thermal conductivity of the nanofins composed of CrO₂ significantly enhances the heat exchange across the microchannel. The proof-of-concept magnetophoretic system can offer a practical solution for the cooling of future compact electronics.